I would definitely want a medical check-up to see if here is any reason for a child of 4 seemingly not wishing to use the toilet. Can remember one of my youngest (and I thought I was well experienced by then), having dreadful problems, crying every time I tried to put her on the potty. Turned out she had a real nasty painful UTI. I should have caught it much earlier, but was so taken up with looking at 'pyschological' problems.
One of my g.daughters could never get clean. She would lie about it, even when we could all smell it - this was when she school age. Turned out she has some sort of syndrome which means that the nerve endings around the anus just do not operate properly to inform her when she needs to have a bowel movement. After several years of different types of treatment, she is now in her teens and has to give herself a 'washout' every other day which is dealing with this.
So, before looking at all sorts of emotional problems, do get the child checked out properly medically.
Parents-in-Law. What do/did you call them?
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