Well, Lou Ann Walker is certainly the protagonist of this story and, as such, has quite a number of positive character traits. As a daughter with two parents who are deaf, Lou Ann Walker fights a battle between her two main character traits: frustration and perseverance.
Another character trait of Lou Ann Walker's is frustration (especially in her young life). This trait takes over Lou Ann periodically and, at one point, she runs from the family obligations because of this frustration. This frustration exists mostly because Lou Ann often had to be the ears and the voice of her parents.
Most importantly, Lou Ann Walker has the character trait of perseverance. Lou Ann is her own person and is determined to excel despite her parents disability. One cannot read her story without noting Lou Ann Walker's accomplishments. She goes to college and succeeds at both Ball State and Harvard. Lou Ann Walker also becomes a successful teacher of the deaf, but works hard to become a New York City journalist as well.
In conclusion, we can't speak about Lou Ann Walker's character traits without mentioning the key passage of the book:
I'd seen plenty of families where there was more communication and less love.
As a daughter with two deaf parents, this key quotation shows Lou Ann Walker's wisdom due to her experience. In my opinion, this wisdom becomes one of her most important character traits that she learns throughout the course of the book.