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.