My dad died when I was youngish, 30. But he'd been close to 40 when he had me, whereas my mum was 22. She is still alive and is now 74. But I'm not 55 yet.
Her parents died when she was around 55, at 85 & 86. I had my DC young so I would hope to still be around when they hit 55, although I really don't want to go past 80 myself. But because I had my DC so young, they did get to at least meet their great grandparents, which meant a lot to me as I was very close to them.