Oh man that's awesome!
My parents are grandparents with five grandchildren and they both said it is one of the best roles to play. They get to be the good-time grandparent and leave the hard stuff to us. I'm close to one of my grandfathers. He got me interested in knives, guns, tools and woodworking. He gave me his whole shop full of tools that I'll cherish forever. We still see each other a couple times a month and it's a relationship I truly value. I wish you well with your little ones!