Susan, my husband's voice was quite raspy. Sounded like he didn't have one for a bit. Truthfully, it's so back to normal that I forgot about that until I just read your post. He also (like I'm betting a bunch of folks) got some nasty sores from the treatment. They also healed but that took awhile. The cans of carnation560 (he had a prescription version that insurance paid for) were invaluable. For awhile it was all he could get down.

You may want to speak to the social worker to be sure she has a good sense of how your sister is feeling. Sometimes,I get very valuable info from the families that really do help me treat the patient better.
Keep in mind though, that it is also so normal to be discouraged and want to stop when you feel so crappy. Just as long as she keeps going...
And,of course, do what you can for yourself. It's so hard to see and hear someone you love so down in the dumps.