Find My

Additionally:

There’s really no such thing as a “FamilyID.”

ALL AppleIDs are intended to be for individuals.

So, the individual AppleIDs are “logically joined” together into Family Sharing.

Family Sharing has additional FindMy features built-in. (very helpful when trying to find your partner’s device - w/o any additional sign-in being required.

See:

Set up Family Sharing - Apple Support

Then:

Share your location with your family - Apple Support

She can sign in to sign in to iCloud.com/find with her apple ID and password

From:

If your iPhone, iPad, or iPod touch is lost or stolen - Apple Support