Their age? Not all of them were thirteen or twelve. It'd have been better if everyone said a specific age or said 'teenager'. Evelyn didn't like to be considered in the same group as a thirteen year old. Like what Simon said.

"Well, should appearance or personality really matter?" she asked after raising her hand. "I mean...she could be older than we even think, yet still look young and beautiful and just have a prideful personality. Really, I wouldn't want to be compared to a Hippogriff either." And she'd feel sorry for whoever did. She wasn't very good with memory spells, hehe. Hmmm if that was the case though, most people would be jealous of that Sphinx.

o_O