My parents were 40 when I was born. I have an "old" family; everyone was and is OLD. While my parents were wonderful and they outlived many of my friends' parents, there is a generational mindset gap. Despite older parents congratulating themselves about how their kids "keep them young" imo there is just something missing for the kids.
I think there are advantages and disadvantages in any parent-child combination. Younger or older parents ... first, middle, or last child ... no situation is ever going to be perfect.