Delete child iCloud.com account created in error

While setting up a child account I was getting an error that the email address wasn't valid so I selected a new one. Once the 2nd email address went through there were 2 new child accounts on my family account; The original that didn't appear to work and the 2nd one that I'd like to stick with. I cannot delete the account from my family share since it has an age of a 12 year old.... How do I get rid of the extra account now tied to my family share???