@RandomUsernameHere
Blossom my MiL** is only 61 and needs a double knee replacement!
Oh gosh, I am 61 and cannot bear the thought of that. I had a (different type of) operation on my knee aged 13 and the experience was horrendous. I hope never to have to have anything like that but have recently heard of a woman in her forties who has had to have a double hip replacement (I see someone else knows another person who has had the same in her forties). You never know what is around the corner.
Sorry I did not mean to turn this around to be about me, I just have a 'thing' about knees due to my early experience. End of now.
I agree with entropynow and Boomhisshiss; everyone is different.
My cousin had a knee replacement in her sixties and recovered well, so have many others. The Queen had one years ago and is fine.
Young and old have health problems but many of them are 'sortable'.
Regarding grandparents,many children grow up without any, some live in another country and are rarely seen, others have died or the family has drifted apart for some reason.The most important people to children are mum and dad.
My parents were older parents, I never knew my mum's father but her mother lived to 92. My father's parents lived to late eighties and 98! My husband had a grandmother who was lovely, she made 100 and knew my children well. She was great fun.
You really cannot generalise but I do feel the op should not receive negative comments, it helps no one and, who knows, she may be fit well into old age. Good luck to her.