REMOVING CHILD Account (my niece) from my Apple Family Sharing Plan (Music). What is the easiest way to remove her?? Why is this so hard to do?

Hi,

I am trying to remove my niece's account from my family sharing plan.

The initial intent was for her to be able to use my Apple Music account so she can listen to music.

I apparently messed up on the setup somehow because she already had an iCloud account.

Now I just want to remove her. I am the admin and paying for it, why can't I remove her like the adult accounts?

Please help me!