<P> The concept that narrowly defines a nuclear family is; central to stability in modern society that has been promoted by familialists who are social conservatives in the United States, and has been challenged as historically and sociologically inadequate to describe the complexity of actual family relations . In "Freudien Theories of Identification and Their Derivatives" he states "Very little is known about the extent variation in the behavior of fathers and mothers towards sons and daughters, and even less about the possible effects on such differential treatment ." Little is known about how parental behavior and identification processes work, and how children interpret sex role learning . In his theory he uses "identification" with the father in the sense that the son will follow the sex role provided by his father and then for the father to be able identify the difference of the "cross sex" parent for his daughter . </P> <P> Historians Alan Macfarlane and Peter Laslett postulated that nuclear families have been a primary arrangement in England since the 13th century . This primary arrangement was different than the normal arrangements in Southern Europe, in parts of Asia, and the Middle East where it was common for young adults to remain in or marry into the family home . In England multi-generational households were uncommon because young adults would save enough money to move out, into their own household once they married . Sociologist Brigitte Berger argued, "the young nuclear family had to be flexible and mobile as it searched for opportunity and property . Forced to rely on their own ingenuity, its members also needed to plan for the future and develop bourgeois habits of work and saving ." Berge also mentions that this could be one of the reasons why the Industrial Revolution began in England and other Northwest European countries . However, the historicity of the nuclear family in England has been challenged by Cord Oestmann . </P> <P> As a fertility factor, single nuclear family households generally have a higher number of children than co-operative living arrangements according to studies from both the Western world and India . </P> <P> There have been studies done that shows a difference in the number of children wanted per household according to where they live . Families that live in rural areas wanted to have more kids than families in urban areas . A study done in Japan between October 2011 and February 2012 further researched the effect of area of residence on mean desired number of children . Researchers of the study came to the conclusion that the women living in rural areas with larger families were more likely to want more children, compared to women that lived in urban areas in Japan . </P>

Where does the term nuclear family come from