14 stone kid. At what point is the mother overwhelmed?

[AB Asks]

A fourteen stone boy who is only 8 years old has been attracting publicity. The boy is four times the average weight for a child his age despite losing more than a stone before Christmas. Reportedly, he struggles when dressing and washing himself, misses school regularly because of poor health and is a target for bullies. His mum has commented that "He refuses to eat fruit, vegetables and salads - he has processed foods. When Connor won't eat anything else, I've got to give him the foods he likes. I can't starve him." What is the best thing to do in this situation?