I've made a flannel quilt top out of unwashed scraps from DD's pj pants, I made it extra large to allow for shrinkage when washed. My problem is I don't know what fabric to use for the backing, flannel or regular cotton? Do I wash that fabric first or wait until after it's quilted and let it all shrink together? Maybe I should wash the top first then put a backing on it? I also plan to use a low loft batting with simple, basic quilting, so it won't be to heavy. Normally I wash my quilt fabric when I bring it home, but I cut these scraps about 10 years ago with no thought to quilting them. All ideas will be appreciated, thanks.