How do you change an adult to parent or guardian?

Read this shortcut to the section of the document about how to choose another approver --> Approve what kids buy with Ask to Buy - Apple Support

How to choose another approver

The family organizer can give another parent or guardian in the group over the age of 18 permission to manage Ask to Buy requests. Only one adult needs to manage each purchase, and after the purchase is approved, it’s final.

On your iPhone, iPad, or iPod touch

In iOS 16 or later:

1. Go to Settings.
2. Tap Family, then tap your family member's name.
3. Tap Parent/Guardian.
4. Tap Set as Parent/Guardian.

In iOS 15 or earlier:

1. Go to Settings, then tap your name.
2. Tap Family Sharing, then tap your family member's name.
3. Tap Role.
4. Tap Parent/Guardian.

On your Mac

In macOS Ventura or later:

1. Choose Apple menu  > System Settings, then click Family.
2. Click a family member's name.
3. Click Parent/Guardian.
4. Select Set as Parent/Guardian, then click Done.

In macOS Monterey or earlier:

1. Choose Apple menu  > System Preferences, then click Family Sharing.
2. Click Family Sharing in the sidebar.
3. Click Details next to the family member's name.
4. Click Edit, then select Parent/Guardian.