Sub Account Settings? Can't friend my son

I gave my son a sub account on the ps4, I remember during the process you could block them from having friend requests, which I did.

I foolishly assumed he would automatically be in my friend list, but he's not. The system won't allow me to send him a friend request, and I can't find a setting for it. Anyone know how to fix this short of deleting his account and starting over?