Family relationships, gender roles and society's demographics changed much as life transitioned from a rural, agricultural economy to an industrialized, urban economy.
In rural agricultural life, families lived and worked together on farms. Wives managed the household as well as doing farm work. Large families with a number of children were common, because children helped in the operation of the farm. Families worked hard, but they did so together as families.
As the Industrial Revolution began, families moved to cities for work in factories. Family members all worked--but now not together on a farm. Family members went to work in separate factories or separate areas of a factory. They worked very long hours, and time spent at home was mostly just for overnight sleeping. Women and children became heavily employed outside of the home setting, as factories hired women and children as much as men -- sometimes more readily so, because they could pay women and children lower wages.
Demographics began to shift also. There was a large increase of city populations over rural population. Family sizes also began to shrink in Western, industrialized societies. In farming life, the labor of children on the farm was worth more than the cost of caring for children. In the industrialized cities, machines were taking the place of human labor more and more, and child labor began to be replaced by machine processes. Birth rates went down in the industrialized world.