One of our daughters carries her ladybug children around the house, gathering them from our country windowsills and re-homing them outdoors when she's done. She'll be five in a few days and this is what I whipped up for her:
Only changes were a generous widening of the neckline because a slip-over-the-head-dress is so much nicer on hot days than a crawling-on-my-back zippered dress. At least in my opinion.