DH's parents were quite interested in our Dad's, had them to stay occasionally etc., though didn't provide regular childcare (nor was it expected).
However, DH's younger brother was MIL's golden boy (a role he very much played up to) so when his daughter she began to take precedence over ours.
My parents were never interested in having much involvement and I knew they wouldn't be. They often impressed upon us as teenagers that we should never asked them to look after our children. That's the way it largely did stay although to be fair, my mother did come down and spend a couple of weeks looking after the older ones whenever I had another baby.
Beyond that, they came down once for a few days when I needed to go into hospital for surgery. Then nothing else. They would ask in a not particularly interested way about them on the phone each week and send money for Christmas and birthdays but very rarely saw them.
My parents were just interested in living in their own little bubble. Everyone else was on the periphery of that, including us children once we were grown up, and even more so their 6 grandchildren (my sister and I have three children each, all now in their twenties). I know they are entitled to do this, and OK, but it often came across as disinterest and unsupportiveness.
I think it is sad that my parents barely knew their grandchildren and I do hope that if I am ever fortunate enough to become a grandparent I will strike a much better balance than they did, without crossing the line into interfering. I want to be willing to give support where I received none, if it is required.