Does anyone eat at night while on Ambien?

Hi. I am asking this question to try and help my sister. I am very worried because she has gained over 100 pounds, much of which seems to be due to unconsciously eating at night. She will even order food and have it delivered, and not remember it.
In the past, with medical supervision, she tried to come off Ambien, but insomnia took over again.
Has anyone dealt with something similar?