If the organizer family sharing wants to remove it self

You have to disband the current family and set up a new Family group with you as the organizer.

Leave Family Sharing - Apple Support --> Leave Family Sharing - Apple Support

Set up Family Sharing - Apple Support --> Set up Family Sharing - Apple Support

From: Hi, how do I make me to family organizer,… - Apple Community

"If there are children under 13 years old, the new organizer needs to leave the existing family, set up the new family, and then the under 13 years old children can be transferred to the new family. Then disband the old family and join the new family."

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

Set up Family Sharing - Apple Support

"Remember, you can only join one family at a time, and you can only switch to a different family group once per year." June 2021

Legal - Apple Media Services - Apple

D. "Family Sharing Rules: You can only belong to one Family at a time, and may join any Family no more than twice per year. You can change the Apple ID you associate with a Family no more than once every 90 days. All Family members must share the same Home Country."

Also note that if you are sharing subscriptions that the individuals may need to make sure they have personal subscriptions during the transition period or their things like playlists for Apple Music and extra storage for iCloud may disappear.

I believe you have to disband the group and set it up again with the new organizer. See Leave Family Sharing - Apple Support.

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