characteristics of nuclear families.A nuclear family is normally made up of a father, mother and their children, whether they are biological or adopted. The nuclear family has traditionally been the basic unit of the larger family structure. It is from the nuclear family that several values such as love, tolerance and coexistence are learned. However, rising divorce rates, delayed marriages and delayed delivery continue to affect the prevalence of the nuclear family. Several factors characterize the nuclear family.
Within a nuclear family is the union between a mother and a father. An existing marriage or legal union between the father and the mother is also a determining aspect of a nuclear family. Also, the father and mother in a nuclear family generally tend to stay together under one roof, despite circumstances such as occasional trips for work. This is different from a single family in which the father and mother of a child remain separate and are not within an existing marriage or legal union.
The responsibilities of running a nuclear family are exclusively the man and woman of the house. Some nuclear families have both parents working outside the home, others work outside the home, while the wife stays at home, and even a small minority ask the man to stay home while the woman works. This is contrary to joint or extended families in which other family members such as grandparents and aunts may take on some responsibilities in the family.
Small and intimate
Modern nuclear families are normally small in size and tend to be intimate. However, there are some slight variations in that some families have a mother, father, and many biological or adopted children. These are also nuclear families, although they are not modeled after the small modern family.
The nuclear family produces the emotional unity of the family structure. Children develop their emotional and cognitive senses from the core of the nuclear family, mother and father. It is also within the nuclear family that the father and mother develop the ability to handle emotions such as fear, anger and disappointment between the two of them and their children. This emotional component is then carried on by the children in their own family and the cycle continues.
The nuclear family is impermanent because at some point the children of that family stop living with their parents. These children move on to create their own families and the strong bonds between their original family and their pro-creationals (the family in which they marry and have children) tend to erode. This is different from the joint or extended family, which increases in size as children grow up and create families of their own.
The Rise of the nuclear family in Mexico
In the field of studies on the family, it is common to hear criticism and rejection of the nuclear family, that is, of the kinship group made up of parents and their dependent children. Their biologist and patriarchal vision about the construction of gender is criticized, as well as the inequality that is established in their internal relationships. However, often when speaking of family the immediate implicit reference is the nuclear family. The study of her, however, has been scant and superficial. What do we understand by nuclear family? How and when did it arise? Does the nuclear family that historians have told us about have the same connotations as the one we observe today? This section aims to describe the process by which the modern nuclear family has emerged in Mexico, taking as reference three analytical dimensions: family structure, family relationships, and kinship relationships. It is proposed that, unlike what has been proposed, the nuclear family, as a framework of sociocultural relations, did not emerge during the colonial period but towards the end of the 19th century. The first part presents the analytical framework that will serve to reconstruct, in the second part, the features it assumed during the colonial period. For reasons of space.
The family: three analytical dimensions
Marzio Barbagli  has pointed out three dimensions under which the family reality has been captured in international literature or how the term family has been understood: family structure, family relationships and kinship relationships. The first comprises the group of people who live under the same roof, the breadth and composition of this group of co-residents, the rules by which it is formed, transformed and divided. The second dimension includes the relationships of authority and affection within this group of co-residents, the ways in which they interact and treat each other, the emotions and feelings they experience with each other. The third refers to the relationships between different groups of co-residents who have kinship ties,
These dimensions can help us organize the cognitive map that has been built in different disciplinary fields about the forms of kinship and family structuring in our country. It allows us to identify the features or aspects that the research touches and to establish a balance about the accumulated knowledge and the lines of research that need to be covered. Taking these three dimensions into account, we will try to reconstruct how the process of the emergence of the nuclear family has been presented in our country. The definition of these three dimensions has been the result of various debates, at the international level, around the definition of family and the historical forms it has assumed. In these debates, the relationship established between these three dimensions has also been discussed.
To understand the importance of these three dimensions in the current analysis, it is necessary to describe the dominant model under which a good part of the sociology of the family was built, the form that the analysis of these dimensions assumed until the sixties of the century. XX and the questions it received in the 1970s. The basic issue can be summarized in these terms: when moving from a simple society to a complex one, from traditional to modern and, therefore, contemporary historical-social formations, the extended family became nuclear. In this transition, the family changed, both in its structure and in its relationships and in its functions. From the point of view of functions, of a polyfunctional structure – unit of production and consumption, holder of the mechanisms of cultural transmission of values and norms, of social integration of its members, of primary and secondary socialization of the new generations, of control of property and satisfaction of the needs of the subjects who cohabit-,
The family lost potential in many of its functions, which were assumed, then, by other agencies external to it – the school, the factory, the market in a broad sense, the Church – and was characterized by an eminently expressive function: stabilization of adult personality and primary socialization of children. The increase in the division of labor, with the relative process of functional specialization of the subsystems that made up the social system and industrialization, was the main factor influencing the change in the family.
The thesis of the existence of a process of progressive simplification of family structures, which still prevailed in sociology until the 1960s, derived from an evolutionary instance that, starting with thinkers of the 19th century, also permeated and conditioned the sociological reflections of the last century, creating a continuity that ideally linked Durkheim –who formulated the “law” of progressive contraction of the family-, with Parsons –who systematized the processes of change in family structures in terms of nuclearization and specialization functional-.
Durkheim  rejected a conception of the family in terms of a natural group and defined it as a socially determined institution. He considered the conjugal nuclear family as the point of arrival of an evolution, in the course of which said institution contracted the more the social sphere with which the individual was in immediate relationship expanded. From the amorphous exogamous clan, which constituted the first domestic political grouping, it was passed to the clan family – uterine or male -, to the undivided Agnate family, to the Roman patriarchal family, to the Germanic paternal family and to the conjugal family – monogamous- modern. This family form was the result of the law of progressive contraction that summarizes and accounts for the evolution that has influenced the family institution.
Parsons  concentrated all his reflection in the context of the American urban middle class, assuming as a center of analysis not so much and not only the family, but the family-social mobility relationship. Indeed, he considered the nuclear family –composed by parents and dependent children-, isolated from the family particularly “adequate” to transmit the entire value system of American society, centered on what can be defined as a philosophy of success , of social achievement. And this was so because the primary result of the family unit, under the sociological profile, consisted in the organization of individual motivation. Specifically, the value of integration with relatives was a result that was negatively correlated with the determination of the acquisitive logic, with the ambition of personal success.
However, and despite abandoning pessimistic evaluative positions on the nuclearization of the family, structural functionalism, whose most representative exponent is undoubtedly Parsons, followed Durkheim’s thinking in its fundamental lines and proposed evolutionary organic “laws” of the modern family. In modern society, the family becomes detached from the kinship and tends to be increasingly reduced to the nuclear family, it is characterized as a private group, it loses potentiality from a functional point of view – preserving a limited number of functions, in particular, stabilization. of adult personality and primary socialization of children – although society depends on these residual functions of the family much more exclusively than in traditional societies.
Nuclear refers to the family group, it denotes a dynamic, procedural characteristic: family forms tend to a slow process of simplification; forms of cohabitation between more conjugal nuclei, or nuclei that include ascendants, collaterals and / or descendants decrease from a quantitative point of view; Parental loyalty and dependence lose centrality because it is not within the parental group that the subject finds security, support, and resources to satisfy many of their needs. The nuclear family, the conjugal family is separated from the kinship, it is individualized with respect to it and this can be seen in the following aspects: a) from the spatial point of view of the settlement, the modern family is neolocal.
At the time it is constituted, it will live in a different dwelling from that of the respective families of origin of the spouses; b) From the material point of view, it is the insertion in the labor market that determines the level of resources available to the family and no longer the participation in a common activity such as the cultivation of the same piece of land that gives of eat several households; and c) from the relational affective psychological point of view, the identity, the security of the subject does not have its roots in the recognition in an ascriptive community – the family – to which one belongs by birth and not by choice.  it is the insertion in the job market that determines the level of resources available to the family and no longer the participation in a common activity such as cultivating the same piece of land that feeds various family nuclei; and c) from the relational affective psychological point of view, the identity, the security of the subject does not have its roots in the recognition in an ascriptive community – the family – to which one belongs by birth and not by choice.  it is the insertion in the job market that determines the level of resources available to the family and no longer the participation in a common activity such as cultivating the same piece of land that feeds various family nuclei; and c) from the relational affective psychological point of view, the identity, the security of the subject does not have its roots in the recognition in an ascriptive community – the family – to which one belongs by birth and not by choice. 
But the postulate about the emergence of the nuclear family did not only refer to the emergence of a particular type of structure. One element that was involved in this evolutionary conception is that the nuclear structure supposes an ordering of the family relationships that corresponds to it, in such a way that as one passes to that type of structure, certain internal family relationships and a disconnection with those of kinship . It is clear that the model assumed that the three dimensions that we have indicated were in close correspondence. From this it derived –as Barbagli  has argued – that it was enough to study one of these dimensions to also obtain the results of the others.
Likewise, the study of these three dimensions – structure, internal and kinship relationships – has not been presented in a balanced way. Durkheim’s and Parsons’ analyzes, for example, made reference mainly to the first two dimensions. The discipline from which it was studied also influenced the emphasis that was given to one dimension or another, in such a way that, in general, while historians focused on structure, sociologists did so on family relationships and began each again to focus on kinship relationships .
The questioning of this model came from different disciplines. From anthropology, the criticism of Lévi-Strauss, for example, gave a hard blow to the evolutionary model. König’s study , from sociology, also highlighted the importance of social class and family forms in history. Within the sociological field there are a series of studies that questioned the claim that the modern family was nuclear and isolated from the kin. In particular, it was put into discussion that nuclearization and isolation of the family —from the point of view of cohabitation— meant breaking the ties with it, total overcoming of loyalty and dependence on ascriptive ties.
These studies focused on the analysis of the third dimension, that is, on family relationships. Along these lines, the debate between Parsons and Litwak can be mentioned, which opposes the concept of the “modified extended” family to the concept of nuclear family . Likewise, studies such as Sennett  and McLaughlin  showed the dysfunctionality and inability of the “isolated” nuclear family to face the urban-industrial context and the importance in this sense of family relations.
The contribution made by studies carried out in the field of history and demography has been very rich and fruitful to the clarification and revision of the evolutionary paradigm applied to changes in the family. The most important contribution comes from Peter Laslett and the Cambridge group in the early 1970s. Laslett’s studies focused on the dimension of family structure. By analyzing the nominative lists of one hundred English communities between 1574 and 1821, Laslett showed that in England the average size of the household aggregate – serfs included – had remained constant – 4.75 members – from the 16th to the late 19th centuries and that the number The average number of co-residents began to decrease progressively until it reached the average value of three. This aggregate was above all of a simple or nuclear type, that is to say, only composed of a married couple and their children, or by a widower or widower with children.
This result was the product of the diffusion among the English population of the neolocal residence model after the nuptials. Based on these findings, he argued that the main family – defined by Frédéric Le Play in the second half of the 19th century as a patriarchal structure, typical of traditional historical-social formations, in which the inheritance was left to a single son of the patriarch – it had never been a relevant family form in European society. Laslett concluded that the nuclear family form had probably been one of the consistent characteristics of the western family system . The nuclear family, then,
Along with the works of Laslett and historical demography, the contribution that a lode of historiography produced is particularly interesting. Authors such as Philippe Ariés , Edward Shorter  and Lawrence Stone  faced the problem of the nuclearization of the family not in terms of analyzing its structure, but at the level of a deepening of the symbolic, cultural, that assumes for man to constitute a family in the passage from medieval to modern and contemporary society. Their studies can be located in the second dimension indicated, that is, in the analysis of family relationships.
For these authors, beyond and despite the structural characteristics of the family in the various European realities, it is possible to pick up an element of sociocultural fracture, between the end of the 16th century and the beginning of the 17th, which impacted on family relationships , modifying the authority and affective relationships between the sexes and the generations; These were slowly assuming a more affective character, of privacy ( “privacy” ). Here it is worth pausing on Stone’s proposal , who argued that the emergence of the modern nuclear family should be traced back to the pre-industrial period.
According to Stone , the family, particularly the English one, had passed through three different types in three different eras: the “ open line family”, Formed between 1450 and 1630, was characterized by the fact that its members, in the highest strata, were subject to strong control by the family and the community, and because generational and conjugal relations were distant. This distancing depended on the prevailing marriage model, based not on the free choice of the spouses, on the high mortality rate that hampered emotional involvement on the part of the spouses, and on the weakly affective personality type, produced by the forms in which which children were raised or educated.
There was no sense of domestic intimacy or need; interpersonal relationships within the conjugal unit between husband and wife, as well as between parents and children, were rather distant, partly because of the omnipresent possibility of imminent death, partly because of cultural models that required arranged marriage, subordination of women, neglect in relation to children, the habit of entrusting them to strangers at a young age and imposing upon them vexatious discipline. Childcare practices, the absence of a single maternal figure, the fact that the will, which was conceived as sinful, was bent with brute force at an early age, as a rule created particular psychological characteristics in adults: suspicion in women. relationships with others, disposition to violence, inability to build strong emotional ties with any other individual.
The ” restricted patriarchal nuclear family”, Formed between 1550 and 1700, was characterized by the decline of the family and the community, by the growing weight of the elemental conjugal unit and by patriarchy, by the power of the male husband-father. The transition to this type of family was driven by the configuration of the modern state and favored by the Protestant reform. Indeed, at the end of the 16th century and the beginning of the 17th, the previous type of family was modified. The sense of belonging to a lineage was lost, the importance of the family and the clientele diminished, and at the same time the State acquired power and Protestantism spread. The most important consequence was the substitution of loyalty to the lineage or patron for that to the state. This resulted in the weakening of the diffuse affective network of relatives and neighbors that had surrounded and sustained the uncertain ties of the family structure, tending to isolate the central nucleus. The process exposed the nucleus to tensions that in many cases it was not yet able to sustain, despite the continuous strengthening of its internal psychological cohesion.
By a paradoxical phenomenon, although at the end of the 16th century the institution of the family assumed new characteristics of sanctity and although moral theologians increasingly insisted on the importance of conjugal and parental love, in that same period the theoretical treatises with full Support from the Church and the State promoted more authoritarian and patriarchal power relations within the family. The propaganda in favor of this internal authoritarianism in the family and its effective reality, so marked among the wealthy classes, also referred to premarital relations among young people, strictly limited and controlled by parents, to relations between husband and wife, in which the principle of wife’s obedience was continually promoted, and to the relationships between parents and children in which it was held that the main purpose of education was to bend the will of the child. In the lower middle classes and in those who work, economic cooperation in the management of family activity imposed to a certain extent sharing the responsibility for the survival of both. On the other hand, however, the children of the dispossessed class enjoyed greater freedom of choice with regard to marriage .
The third type, the ” closed domestic nuclear family”Began to emerge in the middle and upper classes around 1620 and progressively consolidated until 1800. It was characterized by the persistent defense of the confines of which the family unit had been encircled, as well as by the progressive decline of the influence exerted on it. both for the neighbors, as well as for the relatives. This led to attributing greater importance to the internal cohesion of the family, either because emotional ties with strangers diminished or because the pressures exerted by external organized groups were weakened. On the other hand, however, there was a net reversal of the preceding trend towards domestic patriarchy.
Neither the absolute monarch nor the father-patriarch were necessary for the maintenance of social order. From 1700 the statement is evident, between the bourgeoisie and the landed aristocracy, of a new type of family inspired by the principle of affective individualism, of which Stone exposes his particular manifestations. In the first place, the strength of kinship ties had diminished and of them only those with the closest relatives survived. Second, the choice of the spouse was determined more by free choice than by the decision of the parents and was based both on a lasting reciprocal affection, as well as on the calculation of a gain in money, prestige or power. With the exception of the higher echelons of the aristocracy, financial considerations for dowry became less decisive factors in nuptial deals and instead the prospect of future personal happiness founded on consolidated affection was more important. As a consequence, the number of marriages with heirs, of marriages within the branches of kinship, of marriages of young men with notably older women decreased.
Third, the authority of husbands over wives and fathers over children decreased, and all members of the family unit obtained, or sought to obtain, greater autonomy. The first signs towards a trend towards greater equality between the sexes on the legal plane and on that of education were seen, and the rights of each child to obtain a part of the inheritance were carefully protected, although the birthright did not lose its importance. The families of the professionals, The upper bourgeoisie and the landed aristocracy turned their attention to their children, and some of them adopted remarkably permissive pedagogical positions. Among the wealthiest merchants and winemakers, the number of wives educated to possess the social qualities of their superiors, who disdained to participate actively in the economic production of the family, increased. Instead, they occupied themselves with directing the servants, raising children, and a series of entertainment activities aimed at social advancement, whether they were pastimes such as having tea at noon or playing cards. , charities, theater or library visits. Although the economic dependence of these women on their husbands had increased, they obtained a position of greater relevance,
The upper bourgeoisie and the landed aristocracy therefore saw the assertion of a new type of family, with a new function and different relationships within and with the outside: a family endowed with fewer practical functions, perhaps, but with a much greater emotional and sexual commitment. It was a family focused more on the conjugal relationship than on the family and the community; bound by affection or habit; more liberal inside, less patriarchal and authoritarian; less responsible in relation to the marginalized, who were now taken care of by the public authority, but more interested in their welfare; more emancipated when it comes to sex, preferably practiced within marriage, and less repressed; more interested in children and their demands, and less in adults; more private and less public; and, finally, more attentive and able to control procreation and less willing to leave these matters in the hands of the Lord. In short, this type of family was based on the principle of personal autonomy and was held together by strong emotional ties.
These are obviously trends, not absolute data, ”according to Stone. Older customs and values survived for a long time. The extent to which this new model of family was adopted varied wildly from class to class and family to family. Its fundamental characteristics first took root in the urban bourgeoisie and a little later spread to the landed classes. Many other aspects reached the poor only in the 19th century or even the early 20th century. The result was not so much the substitution of one type of family for another, but the widening of the range of possibilities. The variety of family types increased, the reserve of cultural alternatives was enriched .
The ” closed domestic nuclear family ” was already a reality before industrialization and, therefore, was independent of it. The formation of this type of family is explained from the birth of “affective individualism”, that is, from the profound changes caused in the way in which the individual considered himself in relation to society —the affirmation of individualism— and in the way he behaved and felt in his relationship with other beings — particularly with respect to his wife and children, and towards parents and relatives. In other words, the affirmation of affection.
According to Stone, the following changes in family relationships occurred in the transition from the traditional extended family to the modern nuclear one: a) the liberation of the control exercised by the community and the family; b) the passage from a marriage system combined by the parents, based on economic and social interests, to one founded on the choice of spouses through physical attraction and love; c) the relationship between the spouses had also changed, moving from coldness and distance between them to affective warmth, intimacy and erotic passion; d) the relationship between parents and children had gone from the indifference of the former towards the latter, to the care and affection towards the latter.
From the research we have presented, focused on the analysis of the structure or family relationships, another result is derived regarding the relationship between these dimensions, between structure and family relationships. It is not possible to establish a single watershed that explains the change in a single act, of the structure, of the family and kinship relationships. Despite the fact that forays into this field are still open, and that the times and modalities vary according to each country and region, there is a consensus on the matter. Indeed, in the case of England we have seen that the nuclear structure already existed in the pre-industrial period  and family relationships, on the other hand, did not change at the same time but had different rhythms .
Based on these questions, we can conclude the following: 1) industrialization , rather than creating the nuclear family, contributed to its diffusion among social strata and classes that presented other organizational forms, to the point of transforming it into the predominant family form of the Modern society; 2) the three dimensions that I have indicated do not maintain a unique relationship with each other, but it is important to analyze the content of each one of them and, from this, see the relationship that is established. A nuclear structure may contain various forms of family relationships, an extended family may have roots in affective individualism, in the market mentality or in romantic love. Finally, it is also necessary to take into account the relationship and the role of kinship relationships.
The questions that received the thesis on the development of more extensive forms of family to nuclear forms linked to the development of modern industrial society contributed, in short, to disengage the univocal correspondence that was established between them. The relationship established between them is complex, which is why it is necessary to maintain them as dimensions of analysis whose content must be specified in each case. However, these debates served as a catalyst for the development of lines of research that are still open today