Kiki is 11 years old, weighs 11 stone and at risk of diabetes. Although he is obese, his diet is good and he is one of the sportiest kids at school. Rangan must discover why Kiki can't lose weight and come up with a solution quickly to keep school bullies at bay. Kiki's father, Mark, has chronic back pain and suffers from stress. A former athlete, he can barely move on some days and it is destroying his relationship with his son.Hoshi-Rae is a 16-year-old girl with an eating disorder. Her diet is causing her health to suffer and seriously affecting her teenage years. Is the key to her problems her mum Lisa, who has a history of bulimia?