Hi Kimberly!
Thank you for bringing your question to the Disney Parks Moms Panel!
This sounds like a great time for your family to get together at
Walt Disney World Resort!
Guests staying at one of the
resorts on Walt Disney World property are definitely able to have visitors. In fact, your brother can even add you as a Day Guest at the resort to enable you access to a room key.
I was visiting in December and was going to be out all day, so I stopped at the Front Desk to leave my brother's name as a Day Guest. He and his family wanted to stop by to see my resort room. It worked out fine!
If you're driving, you will want to explain to the Security Guard about your situation and be aware that they will most likely ask to see your photo ID.
I hope this helps! Please let me know if you have any other questions.
~Lori