Parents how would you handle this situation that my friend is dealing with?

She has a child that is extremely sensitive. Punishment isn't an option. The little girl make herself sick when she's even yelled at. She'll stop eating and have a hard time sleeping. No she's not minipulating her parents. My friend's husband thought so but they took her to a therapist to find out what's going on and the therapist confirmed that it wasn't minipulation. The child is overly sensitive. Anyway B (that's what I'll call the child) is a really good child but she has issues with bath and bedtime. My friend is stuck on how to get her daughter to cooperate without punishing her. Telling her it's night-night time doesn't help. Her husband wants to ignore the sensitivity and just punish the kid. He's less then patient and suffering from depression. How can my friend handle this situation without having everything fall apart. B has also had some problems because her grandfather abused her when he was babysitting for her in all 3 ways. That was when the problem started about a year ago but my friend didn't find out until B's big sister told her about that and the grandfather confessed on his deathbed.