My peers learned all the unwritten rules of decorum and body language in their homes; they understood what was appropriate to say in certain settings and what wasn’t; they learned both traditionally masculine and traditionally feminine social mechanisms.
Even if my peers’ parents were divorced, and many of them were, they still grew up seeing male and female social models. They learned, typically, how to be bold and unflinching from male figures and how to write thank-you cards and be sensitive from female figures. These are stereotypes, of course, but stereotypes come in handy when you inevitably leave the safety of your lesbian mom’s trailer and have to work and survive in a world where everybody thinks in stereotypical terms, even gays.