DS will be 3 next month but absolutely refuses to spend any time without a nappy/pull-up. A few months ago he happily weed in a potty but doing a poo without a nappy scared him so he now refuses to sit on a potty or toilet or spend any time at all without a nappy on. He's fine with changing his nappy but if I (deliberately) delay putting the clean one on, he gets upset and tries to out it on himself. He won't get in the bath without a swim nappy. I have just backed off completely in the hope that we could try again later when he was ready, but it's been nearly 6 months and he is still scared of not wearing a nappy. Any advice? How long can I leave it before I have to do something?