My sister, her husband and two girls will be traveling to WDW in June. Due to their circumstances this is the only time they can go. My BIL has cancer and is undergoing various treatments. His physicians have said he should be able to do a trip with his family with restrictions... of course taking it slow, trying to avoid long periods of sun exposure, not standing for too long as he tires easy, etc.. He has always wanted to do this trip with his children and is determined to go. The doctors at MD said they could provide documentation to be presented for whatever accommodations are needed. Who would my sister give this to? What can they do and does she need to present this in advance to travel or upon arrival? Advice and prayers are needed. Thank you all.