Ah, parenthood.
(Also, public service announcement, if you ever go to Britain, please do not follow the tiny prince's example and start throwing reverse peace signs around. It will not end peacefully.)
It doesn't mean peace, that's for sure! :P To throw someone the V, or the two-fingered salute-- what Americans would consider a peace sign, but with the back of the hand facing the recipient-- is basically to tell them "See these two fingers? Stick em up yourself." It's extremely rude, comparable to flipping someone the bird... Either the tiny prince doesn't know that, or he knows it full well and finds it extremely funny. Since he's a little boy, I'm gonna bet on the latter. xD
(Also, public service announcement, if you ever go to Britain, please do not follow the tiny prince's example and start throwing reverse peace signs around. It will not end peacefully.)