sexual behaviour out of order
Working with children has often helped me in my life with my Dad who has Alzheimer's (I'm now his full time Carer). When Dad's flies are undone I will be discreet and let him know, however when he does something inappropriate the 'mother' in me pops out and I say something like "No! That's no accetpable behaviour, don't do that agin please" in a sharp, matronly way, complete with shocked face expression. The psychologically ingrained schema (behaviour patterns) from his/her childhood is still there.
Does your dad also have FTLD along with PPA? My wife has both but I think they are generally associated with each other and are a different type of dementia from Alzheimers.
We experienced this too. Shocking and sad. My dad has Primary Progressive Aphasia and they said it's common for the disease.
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