My SO is paying for Family Share, my daughter and I can access him, he can access our daughter, but I am not even listed for him, what gives?

From the linked article:

On your iPhone, iPad, or iPod touch

1. Go to Settings, tap your name, then tap Family Sharing.
2. Tap your name. 
3. Make a note of which Apple ID is listed. You'll need to use this Apple ID to sign in later.
4. Tap Back to go back to Family Sharing.
5. Tap Purchase Sharing and make sure that Share Purchases with Family is turned on.
6. Tap Back, then tap Apple ID.
7. Tap Media & Purchases.
8. Tap View Account.
9. Sign in with your Apple ID. Make sure that you sign in with with the same Apple ID that you use for Family Sharing.

tt2