You get about 6 months of freedom between the kids being off the books and settled before your parents fall apart and fill the worry hole.
Depends on what age you had children to a degree and a bit of luck I would say.
I am in my early thirties and my parents are in their early 60’s. On my side we moved out over a decade ago and grandparents have been in good health ever since but on my wifes side it lasted about 6 years before the parents became a problem.
I do think me and my wife have booked the trend though, married young and had kids young; we laugh about it but we’ve been together longer then we have been apart as teenagers growing up. Most of our friends are only just getting married and thinking about kids!