Family is pretty important in Inkheart, in part because a lot of the main characters are related. Meggie goes on an adventure with her dad, a.k.a. Mo, and her mom's aunt, a.k.a. Elinor. The fact that Meggie's mom has been missing since Meggie was three is also important, and part of the book's mysterious plot.
Other characters have families that are significant to them too: Fenoglio loves his grandkids, so he can be controlled by threats to them, and Capricorn's mother, Mortola, threatens to poison people (and follows through on those threats) in order to remove obstacles to her son's success.
As for those characters who don't have any family, like Dustfinger and Farid, they tend to be loner-types, too, showing another way in which family attachments (or lack thereof) can be a defining character trait.
Questions About Family
How would you describe Meggie's family in five words or less?
We never learn about Dustfinger's family, but what would you imagine his was/is like?
How is Elinor's perspective on family different from Meggie's?
What is Capricorn's family like, and how has that shaped him?
Chew on This
In Inkheart, the more family you have, the more likely you are to be a sympathetic character.
Meggie's dad was all the family Meggie needed growing up.