I think you are a wonderful friend to do this - even if it is driving you nuts!! Your blessings will come back to you ten-fold!!

I have a friend who has done a few T-shirt quilts. I'm pretty sure she uses a product that stabilizes the squares so they don't stretch. It is not pellon, I can't remember the product. I just tried to call her but no answer. I'm not much help am I?

Lots of good suggestions. With the next 4, you might want to use a foundation, especially with bias edges and knits