baby quilts!

I have nearly finished no 2 quilt . Hand Quilting it !!! Not my usual thing but I have tried the silk/cotton batting and found it to be great for HQ. However my question is, the next 2 baby quilts I have to make, are for twin girls. Does anyone have an idea for two, that could ,(maybe ) be made using a positive /negative design so that they will match but be different if you see what I mean. All ideas carefully considered! lol