Well - This is just terrible news - but it could be worse. Your daughter is young and strong and that's what you need to go into battle. That's just what this is: a battle.
Unfortunately, I know a bit about the effects of chemo. The side effects vary amongst the different types of treatment used. My husband never did lose his hair, because the type that he was on does not cause that. David had a shunt installed in his upper chest and he would wear a pump that steadily pumped his treatment into his body for 3 days at a time. Then there was a "break" before he had to have another treatment. This went on for six months or so.
One thing it seems like all chemo regimens have in common is nausea and lack of appetite. This is where you need to be especially vigilant. David got down to 118/119 pounds at his lowest point until we found the key. He would try to eat and I would nag at him to eat but he'd take a few bites and couldn't get more down. Some things that were delicious to him before tasted awful. We finally got him to stop losing weight when we began giving him a special shake every morning. It is basically Instant Breakfast in a milk base but we also added ice cream to make it more like a milk shake and to add fats and calories. Sometimes we'd plunk in a half a banana for additional potassium. You could use different flavors of ice cream and different fruits. Also be sure to give her a good multivitamin.
I'm so sorry that the both of you are going through this. It's miserable, I know. We are here for you. Feel free to PM me if you like.