Great to have those grands in the life of your kids, and in your like too. My favorite "job" is that of poppa. I thoroughly enjoy the time we get to spend with any of the nine grand kids. Also, my Mom (91) is still alive and my daughter and son make sure they and the kids pay her a visit anytime they can. She loves it!
When the Lake Magazine folks did the article on my garden on the pier the writer quoted me a couple of times about the grandkids. I got text messages from daughter and daughter-in-law that the kids really beamed when they read that part in the article.
Keep those kids and old folks interacting!