Kids birthday etiquette question

[charminglife]

Instead of putting that information in the invitation, could you let people know about it when they RSVP? It might be clearer that the party and the circus are two different things and, etiquette-wise, it doesn't look like you're inviting people to part 2 of PTS's birthday party that they have to pay for.

[ringstrue]

is it $15/person? Are kid's her age free?

My only experience with this is Build-A-Bear but that's different because you are paying per kid and not per adult.