Don’t worry about making sure your kids gets a picture with one of the characters. Kids all react differently to Mickey, Jasmine, or the rest when they actually see them up close. Some of them do great, some freak out. If your child doesn’t like one, he probably won’t like the others. Forcing your child to cry and scream through a photo op isn’t fun for you, for them, everyone watching you (who is wondering why you are torturing your child anyway), or for that character who is still smiling–because they have to.
It’s ok to wait until they are older, really.