hello i have a 7 year old girl that has never been for a poo on the toilet .at the time of potty training she had a bad experiance where she was constipated and it hurt her to go and shes never been since .she was precribed movicol but refused to drink it .i also have a 4 year old girl who is still in nappies and is copying her sister . i also have a 1 year old girl who will soon need to be potty trained . any ideas on what to do next