Husband worried about smell

I've known my husband since 7th grade and he was the smelly kid in class. He didn't have electricity or running water at home so he couldn't bath. Ever since he left home he's been worried about being stinky. He has anxiety when it comes to getting close to people because he's worried he's gonna smell bad. He showered 3x a day which is horrible for his eczema. My family is going on vacation and we are all invited. My family all knew him as a child and that he was smelly and know he has this fear of smelling badly so I have no idea what my sister thought it was a good idea to go up to him and tell him he stinks as a joke. All it did was undo all the work he put into getting over his anxiety and now he doesn't want to go because he's worried he will stink. I've been trying to calm him down and convince him to go but he's adamant about staying home now.