Larger Family Plan
I have six children, so a family of eight altogether. Can I pay a little more on my family sharing plan to get the rest of us on there?
I posted that link so you could make a suggestion to Apple.
If you want to see where Apple talks about the limit:
What is Family Sharing? - What is Family Sharing? - Apple Support - "With Family Sharing, you and up to five other family members can share access to amazing Apple services..."