My first idea is set years later Star is a adult with a kid(magic is still around) and after getting into a argument the kid ends up using the wand to cast a spell that reversed the roles of adults and kids now they are in charge and Star is in diapers being treated like a baby despite her age and size.
.that or they make a bet to which is harder being a kid or adult and do this.
Which ever you prefer.
I'm fine being either the kid or Star you can pick.
We could also do this idea but with Hekapoo and her kid.
I also have these other Star VS ideas if your interested
https://diaperedanime.com/forum/show...977/index.html