Absolutely without doubt. I am male 46 year I have a son (19) and daughter (22). I promise that if I randomly pick a happy moment out of my life it will include my kids, I smile when I think about them and I miss them when now that they are back at school. When I think, well they are now living their own lives now and not around as much, I remember how proud I am of them and what they are accomplishing.
As for me getting Alzheimer’s at 65, my thoughts would be to enjoy my children and hopefully grandchildren till I no longer can function. Then it’s time to “step away”, no need to be living without life. All that life is, memories and future expectations.
As for the kids potentially inheriting it I’d have to say life is a crap shoot but they would have many years to enjoy that life if that were the case. I know they would have the strength to deal with it. After all life is what you make it with a few bonus curve balls and sliders to keep you on your toes.
Another thought on your children dealing with parents falling ill at an advanced age (65 and above?? I guess). They will get over it, it hurts but it’s one of those inevitable things of life that you are hard wired to deal with.
Don’t let a potential future issue rob you of the enjoyment of the present.
There’s a podcast (Sad Oligarch) that outlines a lot of these “mysterious” deaths in Russia.