Baby snake is DYING and I need help?

My girlfriend and I are watching two snakes for a friend (baby ball pythons), and we have had some serious problems. They apparently have not eaten for 6 months, due to various health issues, and are meagerly thin. One of them ped away just hours after we took possession of them, and the other one is on the brink of death. We need him to eat, or I know he will die. I need some help, because I do not know what to do, and my girlfriend will not be able to fathom two snakes dying in her care.