With the age they are, the I Spy quilts would be fantastic.
Yes, same but different .... different border/sashings.
I would probably use the same fabrics, and just reverse the placement of them within the quilts.
I might go a step further and use different I Spy fabrics for each quilt.
Same themes? or two different themes? Would depend on what fabrics I had to work with.
That way they would have two totally different but the same quilts ....
..... and two different I Spy games to enjoy as they grow together.