So you want to enable Family Sharing's "Ask to Buy" to buy feature but your child is on an old Apple ID and you can't find a way to go back and change their birthday to make it work? You're not alone. And while there's no easy fix, there is a way to work around it. As long as you've got an open on your Family Sharing account, you can swap your child's old Apple ID to a new child ID, and get Ask to Buy working the way you want it to.
It's important to note that this process can't convert your child's existing Apple ID into a child ID. It creates a new Apple ID and transfers all their data across. That means they won't lose any backups or purchases, but there are still some downsides. For one, they'll have a new email address, which means a new ID for mail, iMessage, and FaceTime. (You can forward email and enable multiple addresses for iMessage and FaceTime.)
Before you begin
Here's what you'll need:
A completely open slot on your Family Sharing account
The username and password for your child's existing Apple ID.
You'll need to have room for both your child's old Apple ID and new child ID on your Family Sharing account to maintain access to old iTunes and App Store purchases, so it's really important to make sure you have an open slot available.
1. Create a new child ID
You'll need to create a new child ID, and you'll need to create it a family organizer's devices.
2. Back up your child's iPhone or iPad to their existing Apple ID
Before transferring data, you should always make a backup in the event something goes wrong. If you don't know how to manually back up to iCloud, you can follow our guide. You're can alternatively back up to iTunes if you prefer that method or are already doing so.
5. Sign out of the old Apple ID on your child's device
You'll need to sign out of your child's old Apple ID. To do so without losing any additional data:
Launch the Settings app.
Tap on iCloud.
Tap on Sign Out — it's all the way at the bottom.
Tap Sign Out in the popup menu to confirm you would really like to sign out.
Tap on Delete from iPhone to confirm that you are aware items such as iCloud Photo Library and Documents and Data will be removed.
Tap on Keep on My iPhone to make sure you maintain existing contacts, calendars, etc.
Enter your child's iCloud password to disable Find My iPhone.
6. Sign into the new child ID
Once you are completely signed out of iCloud on the old Apple ID, you can sign into iCloud again with the new child ID you created in step 1. If you are asked, choose to Merge data from the device to the new Apple ID.
Launch the Settings app.
Tap on iCloud.
Enter the new child ID credentials and tap on Sign in.
7. Create an iCloud backup on the new child ID
Repeat what you did in step 2 but perform the backup using the new child ID.
This simply ensures that all contacts, calendars, reminders, and other items are backed up to the new ID. From that point forward, all data on your child's device will be backed up to the newly created child ID.
8. Keep both Apple ID's as part of your Family Sharing group
As long as the old Apple ID and the new child ID are both added to your Family Sharing group, everyone should have access to all the purchases made under the old account. The only difference is now you've got the ability to enable the option for Ask To Buy since your child is now set up as a proper child ID.
9. Transfer photos back to your device
If you're using iCloud Photo Library, you can upload your child's photos to the their new account:
If you're not using iCloud Photo Library, you can sync the photos back over USB.
How did it work for you?
This is not a simple or convenient solution, but it gets "Ask to Buy" working and it lets your child keep their previous iTunes and App Store purchases. If you try it, let me know how it works for you. If you've found an easier or better way, be sure to let me know that too!