Family Sharing
Do I need to be related to the individuals who are in my Family Sharing?
iPad Pro, 12.9-inch, 6th Gen, Wi-Fi
Question marked as
Family relations are not a requirement, and no such checks are done.
Family Sharing and all its related services may be aimed at groups that are much like family households, but any 6 people with Apple ID accounts for the same country can form a group, and e.g. share these sharable subscriptions.
Learn more about what you can do with Family Sharing - Apple Support
Set up Family Sharing - Apple Support
Add a family member to your subscriptions from Apple - Apple Support