Thanks for the link Corky. I'm afraid her linen is much coarser than the ones used on the site. She did test wash one piece and the painting did really well, but it was terribly wrinkled.
I had a chat with her today and she said she knows the boys will say "Oooh, nice", fold them up and put them in the closet. But she really wants them put into a quilt. So I put together one top this afternoon. The pieces are not straight and are not painted straight on top of that, but I sashed them with black and got them evened up. Didn't put the border on yet, I didn't want to have to take it off if she doesn't like it. All things considered, I'm pleased with the way it looks. Quilting it may be another matter ...
More updates after she sees it tomorrow.