A quick update:
My family got into Thailand and took a bus out to Khaolak beach. They knew that there was a big media event planned, so they visited the day before. They could see all the stages being put up, so they steered clear. They weren't at the beach the actual day of the memorial, and when they had lunch with the state department representative afterwards, he said they made a smart choice. The crowds were so huge that it took many (4-5?) hours to empty out along the one road afterwards.
My stepsister with cancer had a leg swell up on the flight so much that it left her with stretch marks, and was immediately rushed to a hospital when they landed. The hospital wanted to check her in for the visit, but she declined and instead had them operate to put in drainage and whatnot. After 3-4 hours, they left and did the trip. During, she seemed to have a boost in spirits, the swelling went down, and in the end, she was really happy to be there. Looks like she'll be coming home.
My dad got back yesterday, and the rest are supposed to come in during the next day or so.