Hi Shelley,
Welcome to the Disney Parks Moms Panel! I love that you are using
My Disney Experience to manage Fast Pass+ selections!
As long as your sister is connected to everyone through her My Family & Friends List, she should be able to manage
Fast Pass+ selections for them and to include them in
advanced dining reservations. If she needs to add folks, she can go to the My Family & Friends List in My Disney Experience, click on "Add a Guest." If it looks like she is already connected to everyone, click on the update link beside each name and then, to share plans, check the box that says "All Plans." Be sure to save your changes.
If she is making Fast Pass+ selections for everyone, be sure that everyone has their tickets linked in My Disney Experience. When I have been involved in group planning, we have occasionally had difficulty making Fast Pass+ selections for everyone because, inevitably, someone does not have their tickets linked in My Disney Experience when the person making the Fast Pass+ selections is online, trying to make them.
Shelley, if your sister continues to have problems seeing other family or friends in My Disney Experience, she can contact Website Support at 407-939-4357. One final tip - we always purchase Memory Maker. When traveling with a group, your entire group can share one Memory Maker!
Magic, memories and Minnie Mouse hugs,
Donyell