I couldn't find that much but I found the same question as yours and this is another person comment. :3 hopefully that help :D
A diet that can lower your stress looks like something with a lot of fruits and vegis. Making sure you get a least one hour of exercise a day. Plus drinking tons of water and a some juices. Foods I'd consider would be pineapples, strawberries, bananas, cucumbers, carrots, and etc.
It depends if you an athlete, if you workout, or if you do neither of those things. The average 16 year old that doesn't exercise regularly should consume anywhere from 150-350 grams of protein in a day.
Attend doctors appointments with the mother to help listen to treatment options, ask questions, and discuss any alternatives they can consider.
that dont make sense sorry