First, sharing an iPad with a single AppleID is not recommended - as there is every risk of sensitive and/or personal information (such as account passwords) being inappropriately shared.
The Golden Rule: Don’t share an AppleID between users. Each user should have their own AppleID for their own exclusive use - linked to their own primary email (and secondary/recovery email addresses and trusted telephone numbers).
You would be best advised to separate your digital identities and configure a new AppleID for your granddaughter.
After separating your identities, you can continue to selectively share purchased Apple Services, Subscriptions, Apps and Media using Apple’s Family Sharing features:
Family Sharing - Apple
Set up Family Sharing – Apple Support
Share App Store, iTunes Store and Apple Books purchases with Family Sharing – Apple Support
How to create a new Apple ID – Apple Support
https://www.imore.com/how-set-up-family-sharing-iphone-ipad
Purchased Apps, these are forever tied to the AppleID account from which they are purchased.