This post by Angela Kulig made me think about something that actually plays a major role in the lives of most of my characters - family conflict. Angela's post touches on birth order and how that affects the way a character behaves (someone in the comments brought up the good examples of Katniss/Prim from Hunger Games and the Weasley kids from Harry Potter). But let's look at the larger picture here - how can family affect/influence/conflict your characters?
In one of my stories, a son who has been declared a bastard by his biological father because he's not "male" enough (he's fairly androgynous due to his mixed race courtesy of his mother's bloodlines) watches as his mother is beaten to death by the father who disowned him. In another, one of my characters is adopted by someone completely out of her race/nationality and brought up in a manner unlike her own society after wandering away from her home and getting lost. A third example would be a son born to a mother who is one race and raised to be accepted by a race so alien to his mother's own upbringing that there's conflict between her and the society she's chosen to live in about how he should be raised.
In each of these examples, we can see how a family situation can shape a character's beliefs. Raghnall hates his biological father for his mother's murder, but he also hates his mother for staying with her abusive killer when she was told she could return home by her family. He's later rescued by the group of assassins sent to kill his father & his half siblings (Raghnall's mother was his father's 3rd wife) and finds a father figure in one of the masters of the Order. Anila comes from a primitive race with little true affection from her parents but quickly acclimatizes to living with a far more civilized group and actually comes to love the ways/customs of her foster father's people. She also develops those attachments to home, family, and community that aren't as strong in her native race. Reidar must reconcile his racial tendencies (which are rather prominent) with the societal demands of the land his mother lives as a refugee in. Reidar's mannerisms are heavily influenced by the man his mother brings in to help raise him as well as her holding to certain customs from her homeland. How each of these characters views the world is heavily influenced by the people who raised them.
What about characters that have no family ties? The best example of that would be Scat from my Only A Name story. She's a very young child when her world is turned upside down and she's torn from her parents by a war she knows nothing about and is sold as a slave. She grows up in that slave environment before escaping a death sentence for her peculiar heritage that she inherited from her birth parents. She encounters others like her in the sense that they're all running from their own deaths at the hands of those who would kill the fledgling race that she's a part of, but none of them are exactly like her - though they have several escaped slaves among them. She feels isolated and alone because she doesn't remember/understand the concept of "family" and "community" that binds the group together.
Now, I do have characters that come from "normal" backgrounds. Jerryth's mother and stepfather (Jerryth thinks he's his biological father until his real bio dad shows up when Jerryth's eighteen) have two children that are younger than Jerryth. He's the oldest, so he's responsible for them. A lot of his life revolves around the lives of his two younger sisters. Meg cherishes the memories of her life with her older sister and her younger brother. Pha Lin is her younger brother's staunch defender and main protector. Algethra's bond to her twin brother Jes is what helps her survive some of the worst times of her life. In each of these situations, it's the bonds of family that provide the anchor and in some cases the main backbone for the characters.
How about your characters? What is it about their family life (or lack thereof) that motivates them?