We are going tomorrow with a group of 12, made up of 3 different families, and I'm in charge. Three of the children in our big group have accounts managed by another adult BUT those children appear in my Friends and Family list (as well as under the list, "My Planning Party: Reservations Shared with My Family & Friends" when I log in on a web browser). So far, I have been able to book ADRs and park reservations for those children, even though I do not manage their accounts. I'm hoping/assuming this would also be the case when I try to reserve LLs tomorrow morning. None of us are staying onsite, btw.