Richard Peck also wrote a very funny, offbeat YA book called "Secrets of the Shopping Mall", which deals with conformity and resisting it. IDK if Jensen's niece would like it, but you probaby would, lol. Teresa and several other female characters are very individual, and strong in their ways.

M.M.Kaye wrote "The Ordinary Princess", which deals with Amy, the princess who is exactly that, and it's full of charming illustrations, too.