In structural functionalism, a society can be conceived of as an organism and all of its various institutions can be seen as the organs or parts of that organism. Like our lungs and hearts and arms, each part of the society has a role that it must play in order for the society as a whole to be healthy.
If we think of society in this way, then we need to ask what the family does that is necessary for society. Here are some things it does:
- Allows for procreation and the care of children. No society can survive if its people do not reproduce. Families facilitate reproduction and ensure that the offspring are cared for.
- Socializes offspring. Not only does it allow the offspring to be born and cared for, it also makes them into members of the society. Parents teach their children what is expected of them and how to behave in their given society.
- Sexual release. Some scholars cite this as an important role of the family, preventing the sorts of ills that come about from (in particular) sexually frustrated young men.
In these ways, families play (according to structural functionalists) an important role in society.