If I had to guess, there were two schools of thought as to how to take care of him. John was like fuck it, I want to go out living and enjoying life and the son was probably cool with that. Meanwhile, the daughter was trying to figure out how to best keep him around as long as possible, even if that meant him being miserable.
I'm hoping that was the main reason and not some money shit where she was trying to make sure she got her cut.
