Watch the Video on this FAQ: Tourist/Visitors visa for people
with special needs or challenges
Since Trump administration has proven to be extremely hostile to immigration, both legal and undocumented I cannot predict what the consulate is going to ask. My advice would be to go ahead and apply for her like it is a normal application. Now I also want to add that any people with special needs or challenges as long as they don't pose a threat to the US people or their property they should not have any extraordinarily more difficult burden to carry than anybody else but medically they might have to prove that they can be taken care of. FAQ in detail...
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