What a sad situation! I honestly don't know much about this kind of a situation, but I think it will take time for him to adjust. He probably isn't used to being able to trust adults so I think it will take a lot of love, and patience. You will probably have to gradually instill better eating habits in him, keep trying different things, a little at a time, until he starts to respond. Healthy fats - yogurt, beans, cheese - would be good in adding some weight if he will eat them. And I can't imagine how frustrating this will be for you, but you have to make sure he doesn't think he is doing something wrong. It isn't his fault he was raised this way thus far. As for keeping him up longer, maybe just very gradual, ten minutes at a time, he can adjust his sleeping patterns. Making him stay in bed in the mornings even if he just reads or plays? I saw a clock for kids at onestepahead.com that has a picture of night and one of day, and it changes so they know in the morning when they look at it if its time to get up yet or not. Maybe something like that would be helpful. I don't know. This will no doubt be a long transition for you and your family but you have the opportunity to truly change this child's life for the better, so don't give up. Kids overall can adapt quickly to new situations, so just try to be patient and consistent, you'll get there. Best of luck to you.