Just give LLD's sitters some space and they'll set up a "pop-up child center" that will entertain kids for hours on end. Expecting babies at the party? They'll bring infant toys and seats. Have a few arts-and-crafts lovers? They'll set up a jewelry-making station. Want to transport the kids to a fantasy world? Princess, safari, and fairyland entertainers will help them imagine they're there. And when the kids look tired — but the adult party still rages on — they'll get the kids cozied up for a midnight movie fest. With a one-to-three sitter-tot ratio, kids are carefully watched while Mom and Dad party the night away. But all of this fun comes at a cost — a high cost. Kid Zones start at $500, and the prices quickly climb as more activities are added to the package.