How do I stop my contact from showing up in my other devices connected to my Apple ID

You need to use Family Sharing and create her own Apple ID, based on her age. See this about using Family Sharing. Set up Family Sharing - Apple Support

You can’t. But your Apple ID is personal; you should not be sharing it with anyone else. If you share an Apple ID bad things will happen, this being only one of them.

Don't share your ID with anyone. Even family.

You mean your individual contact card? Are you using iCloud Contacts on these devices?