Have you considered using fleece instead of a back and the batting? Since this is donation, you might be looking for the least expensive way to finish the top and this will accomplish the task and help with price, especially since fleece is on sale at a good price now that it's out of season.

Thanks everyone...looks like I'll be ordering the Pellon from Walmart and giving it a try.
Illinois....I've read of people using fleece for a backing, but I guess I'm old school and think that a batting and backing makes a nicer quilt. IMHO.

For baby quilts I often use flannel for my batting. It gives enough body to be used more as a blanket. I often use flannel on the outside of the quilt as well. I watch for it to go on sale at JoAnn's. I don't care for much of JoAnn's fabrics quality wise but their snuggle flannel holds up really well. I've made burp cloths from it and they get a lot of washings so after that I trusted it enough for a quilt.

Hobby Lobby... buy in bulk & use an on line 40% off coupon
https://imgprod60.hobbylobby.com/sys...05_20_2018.jpg

Hobby Lobby has Warm & Natural in bulk

My favorite baby quilts were from my Aunt. She made a top and backed it with flannel. No batting at all. The quilt draped softly around the baby.