They don't really work in years, they work in generations (well, duh). So GenXers are the children of the boomers, and millennials are the children of GenXers. By then, any correlation with years gets muddied due to the fact that (these days) parents' ages can vary wildly. Back in the boomer days, you were more likely to get a man in his mid to late twenties marrying a woman in her early twenties, and popping out a couple of sprogs straight away.
The "Greatest Generation" thing smells of WW2 celebratory bollocks. I bet the Germans don't call them that.
Parental ages have ALWAYS varied wildly.
The large Victorian families often had older children old enough to be the parents of the youngest.
I'm a boomer, born in 1958 to parents who married the previous year.
Kid Brother was born in 1977, when the other 5 of us were all in double figures.
Kid Brother's kids are aged 3-14…
My sisters kids are aged 24-36..