Take a photo right after your baby falls asleep on the night before his birthday. Then you can add this picture to his baby book. This is guaranteed to become a beloved traditional photo you take every year on the eve of your child’s birthday.
Write a letter to your child or grandchild each year and include money for grad gift. I like this idea of writing a letter, and even adding money, but I think it'd be better to go longer than a grad gift. Wedding, first home, first child?