Hi Elizabeth~
What a wonderful idea you have. I work in product development and I have made personal stepping stones just like what you would want to do.
If you have anything like any kind of trinket (a key, grandma's thimble, coins from grandpa, anything that would embed itself in the stepping stone mix) would be a great personal addition to the stone.
We have a special stepping stone mix at your local major craft store that is specially formulated to be able to hold writing. We also have stepping stone stamps that you could use to write out their favorite sayings or "In loving memory of", or whatever you are inspired to write.
Also, we have the family photo stone that contain acrylic domes to be able to print out photo's and have their photo's or whatever photo's or special papers (a piece of grandma's gift wrap she gave you). The kit comes with special stickers that have a sticky front to be able to put small photo's or papers to the domes and use them in the stepping stone. The possibilities are endless.
If you have a broken piece of grandma's china that you don't know what to do with, you could break it in pieces (please use safety goggles) and use it in the stepping stone.
I hope that helps give you a few ideas on what to do and I know whatever you make will be special. If you go to
www.milestonesproducts.com, you can see all of our kits and maybe get a few more ideas. Whatever you do, it will be great.
Best regards,
Sandy P (product development)