Will a person's true nature come out? *may trigger*

Hi,
Can someone please answer this question? Can a person's true nature come out when they have alzheimer's? This is about my mother. Please read about her here -
child-abuse/topic205164.html

So far as I can see, her jealousy and hatred of me does not emerge unless she is lucid and know its actually me. She is not that far gone. She can eat by herself, can talk. She just won't remember what you said by the time you get to the second sentence. Does not recognise anyone.

So because she is "nice" all the time in this alzheimer's state, my dad thinks she is a nice person.
Anyway, hope someone can shed light on this.
Thank you.

alzheimer's disease is a chronic neuro-degenerative disease. however it affects people, what's left isn't them anymore. it's as simple as that.

by the way, my father has it. i care for him. he's no longer manageable without his medication.