Is a family a main source of socialization in a society?

Families certainly are important in society. Unfortunately, many come from disfunctional families, but, some are lucky to have a fairly normal family with love and affection. We all have a need to belong. One thing I learned that sometimes when someone's family life doesn't work out (with a mother, father, etc.) and you are older there is nothing to say you can't find affection from another family. I have a girlfriend in her 40s and her parents passed away and she has no relationship with her 2 sisters and 2 brothers, so she basically adopted my husband and I and we love it and so does she, her husband and their daughter (our Goddaughter.) Even animals live in packs because they need each other, so I can well understand why we need a family of sorts. Not only do we need family for survival, we need a companion or two to help us out when we need it.