A Game of Thrones
How we cite our quotes:
Ser Waymar Royce was the youngest son of an ancient house with too many heirs. […] Ser Waymar had been a Sworn Brother of the Night's Watch for less than half a year, but no one could say he had not prepared for his vocation. (1 Prologue.14)
In the Prologue, we're introduced to two important family issues: (1) some families can't take care of all their members; and 2) the Night's Watch thinks of itself as a family of "Sworn Brothers." This will be very important later, when Jon is trying to figure out where he belongs in the world.
"You have five trueborn children," Jon said. "Three sons, two daughters. The direwolf is the sigil of your House. Your children were meant to have these pups, my lord." (2 Bran 1.69)
The symbols and mottoes of each noble house are important for the characters, and Jon uses that fact here to manipulate his father into letting these direwolf puppies live. The fact that Jon cares about the puppies and about his half-siblings shows what a great guy he is. And, as Bran notes, the count – five puppies, five kids – only came out right because Jon didn't include himself, since he's an illegitimate child.
"Sometimes I'd imagine my father burning. At other times, my sister." Jon Snow was staring at him, a look equal parts horror and fascination. Tyrion guffawed. "Don't look at me that way, bastard. I know your secret. You've dreamt the same kind of dreams." (14 Tyrion 2.41)
We'll let you decide whether Tyrion is right about Jon. But this is a clear introduction to the issue of family violence and tension. (Tension is the polite word for imagining your father burning to death.) The Lannisters and the Cleganes are probably the clearest examples of families with major issues. But then again, Sansa and Arya fight all the time, too; and Sansa and Eddard have their differences; and Catelyn and Eddard and… you get the point.