I found Card's forword to Speaker For The Dead quite interesting. (I was going to write about this, and now you've brought the topic up...) He talks about his intent for the whole series, how he was trying to establish something that no one had ever done before in science fiction - write about the establishment of family.
He makes the point that typically all fiction is adolescent. Not in the sense of being "immature" or "for adolescents", but in the sense that the hero is always a loner, a "Lone Ranger", going out into the universe and having exciting adventures, visiting a place and doing Great and Good Things, then moving on to the next adventure. Quite right that this should be so, for when we turn to fiction, we are typically seeking something exciting, far from our normal humdrum life. But still, that hero never lays down roots, never settles into the one place and becomes part of a family for whom he is responsible.
Hence "adolescent", for it is the adolescent, in the generalised sense, not merely teenage, who has the freedom and the energy and passion to go out and live incredible adventures, to move from place to place doing good or seeing new things. Some people, Card suggests, in fact never leave the adolescent phase, never stop and become responsible for other people. It is this, he says, the stopping and belonging and caring for others, that makes one Adult, done with adolescence.

Smart man, that Mr. Card.

Fod