Why my Father in law pees and poops on himself.

It is exasperating when they do this, but do try to be a bit more respectful to him, even if you are feeling angry. Learn about incontinence and dementia. Is your FIL staying at home or is he in a facility? If he is at home, perhaps a facility would be the best answer. People there should be trained to deal with these type things. I'm sure they also get exasperated, but they are paid not to show it. It's all just part of the job.

I think if you are educated enough to navigate the web then you should know enough to state your question in a less offensive manner. And since you have found this site you should be able to read and learn about the physical effects of dementia. It is not just being a little bit forgetful, it is a progressive brain disease that slowly destroys the initiative to help yourself and can result in the inability to know how to use the bathroom properly, or to get yourself there in time to avoid accidents. Put the man in incontinence briefs and educate yourself about ways to get him help... beyond the toileting issues he probably needs help cleaning up after himself.

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