How to delete a child's Apple ID Account

hpt192 wrote:

I would like to delete my child’s Apple ID account

Are you asking how to remove the child account from Family Sharing? Or how to delete the account entirely? If the former, you can only move it to another family sharing account. If you don't want to do that, you'll need to contact Apple Support for assistance. You can use the Support link at the bottom left of every page of these forums.

If the latter, see the information at the bottom of this article:

Move a child to another group using Family Sharing - Apple Support

how do I delete a child account - Apple Community