We've had friends who are grandparents, but they've always been significantly older than we were.
Today, I learned that friends who are, yes, older than we are but not really all that much (five-six years, tops) have become grandparents of a baby girl. We went to their daughter's wedding.
On February 5th of this year.
Yeah. Wow. No shotguns involved, since we got invited at least a month before, but wow. I think they can look forward to many grandchildren.
Anyway, mazel tov!