How long would her stay have been? I only need it for one line (mentioning how she was away for X amount of time), and I can work around it. The character in question did not have a very severe case; it was caught pretty early, and she's shown response to counseling.
(Also, if anyone in here has more experience with eating disorders and wouldn't mind giving a quick read-over when this is done, I would love you forever. It's a one-act play about the girl's internal conflict and her family's conflict when she comes home. It's something that I have limited experience with, and I want to do the topic justice.)