How do I potty train a 2.5 year old who has suddenly developed a fear of being without a nappy on? She was fine at being naked and using the potty sometimes but she’s suddenly refusing to take her nappy off and trembles and screams until she has one back on. It started after she weed in the bath. No-one made a fuss in any way but she freaked out and now won’t be without a nappy. She won’t bath, shower anything. Any tips?