My 18 year old son refuses to visit my parents in India. He is the only grandchild and last saw them 5 years ago. He has had gastroenteritis each time he has travelled there and it is boring for him as they are old , infirm & hard of hearing so communication is a problem. No young people his age or that he feels he can relate to. But we feel he needs to see his extended family & cannot cut himself off. He has huge anxiety and a phobia about travelling to India. He is still financially dependent on us as he goes to university . Would it be unreasonable to withdraw all support unless he agrees to go?