twoblessings

I am making a baby rag quilt and am appliqueing on a few of the blocks (3-5 blocks. not sure yet). Anyhow, my rag quilt is 3 layers of flannel. When I don't have appliqueing on my block I quilt them with the traditional X. I want to leave the X off of the blocks I have appliqued. Can I applique through the first two layers of fabric and then just add the last block (the back side)? In othere words, my back side block wouldn't be quilted to the other two. Will this work? Does it have to be quilted? My blocks are appx. 7" from seam to seam.

thanks so much,
twoblessings