Claire, GPs need plenty of vitamin C so encourage your shy little one to eat by offering him a nice wide variety of fresh fruit and veges every day. He will soon show you which ones he likes. It's unusual for a piggie to be a shy feeder, cos they generally are little eating machines. Maybe have his general health/teeth checked? Pineapple I know IS good for rabbits (it apparently help prevent furballs or fur blockages or something). About the tops and about banana skins, I don't know. Banana is OK in small quantities (can be fattening).