Changing from an adult to a child apple id
Can you change the birthday from an adult to a child. I want to keep the same Apple ID. ?
Yes. See the following from Update the birth date associated with your Apple ID - Apple Support
To change a birth date to any age below 13,* you must be a member of a Family Sharing group, and your family organizer must approve the change. After you change a birth date to any age below 13, you can't edit it.* Learn more about Family Sharing.
- Update the birth date.
- Follow the onscreen steps to send an email request to your family organizer.
- Your family organizer will get an email with instructions to approve the request.