How to express kids are invited, if you watch them

We are planning on inviting all the kids in the family, which works out to around 35. We couldn't figure out a way to split them up without splitting families, so it's all of them. The venue has a rule that children under 12 must be supervised at all times. I want to clearly state that on the invitations and website, but I'm not sure how to word it. More specifically, there is a blended family with 7 kids, 4 are under 12. I'm most worried about them and hoping that by putting this in the invitation, they'll decide to leave the kids at home (which isn't uncommon).


If we said no kids, we'd still have to make an exception for several family members traveling from out of town, whose go-to local babysitter will be at our wedding.