Toilet training problem. Child refuses to switch to underpants
We are trying to toilet training my kid and are having a hard time. Some days they will wear their underpants no problem and won't want a nappy, other days they scream bloody blue murder refusing to give up. We started six months ago and managed to get them to wear underpants until they needed a poo, then they insisted on a nappy. It got to the point they were constipated from holding it in. We took a break because of other issues and have been trying again for the last three weeks. Every second day it's a struggle to get them into underpants, even if we get them on, they will take them off, get distressed, screaming and shouting etc.
They're about to start back in school and it's be fantastic if we had this milestone out of the way for them. Anyone any advice?