I think it's a great idea - I would so love to know more about all my grandparents, now that I am one, and have a little time on my hands. Things about how they were as persons, or as children- I am so curious, and they are gone, gone, gone. I moved away with my husband after we married in our twenties, and I never really even got to know my parents as "adult people" in their own right - wish I knew more about them too. So shed a little light for this young one. And don't worry about when or if they'll be interested. At least you've done your part of the deal!