A TRIBUTE TATTOO FOR MY 2 KIDS....NEED SOME IDEAS PLEASE?

I have a 3 yr old girl and a 1 yr old son. I would like a tattoo that is more than just their names and birth dates but I can't think of any good ideas. I have looked online but its hard to find anything but portraits of children. I'm trying to think of a different way to tribute the kiddies without it looking like any ordinary tattoo. Oh and I would like it on my upper back or shoulders. Thank you for your ideas, I really appreciate your time.