My 4yo daughter has never been a good toilet girl but just recently she is having skidmarks in her underwear everyday. She says she needs to go do a poo everyday but hardly ever succeeds and ends up sitting on the toilet all day.

I think its the lack of food she eats. We are trying to get her to eat veggies and meats so we will keep at it. Rewards dont help. Maybe instead of offering rewards we can threaten to take toys away?