My nephew is 15 and uses a wheelchair. When he gets this sort of thing, he looks the person in the eye and says, "Don't be silly!"
Tactful, he is not.
When he was five, he was cornered by a woman with a religious mission. She kept telling him, "You need to praaaaaayyyyyyy to Jesus for healing! Just praaaaaaaaayyyyyyyyy to Jesus and He will lift you out of that chair!"
Nephew side-eyed her and said, "It's selfish to pray for something for yourself. But I'll pray for you if you want."
The woman just stared at him, floundered a bit, and left.