I understand this is a heartbreaking situation. It sounds like their minds are fine, but they are losing their physical abilities, though it isn’t clear if your Mom’s mind is 100%, due to the stress of your Dad’s fall. Trust me, they are aware of their weakening, and are terrified of losing their independence. Reassure them. Let them know you want them happy. I remember every time I would say goodbye to my Mom, after visiting her in her house, I would be afraid the next time I’d see her, she’d be dead at the bottom of the stairs. Let them know your concern is for them. Let them help with a solution.