My friend and blog partner just did an in-depth experiment for marking pens for a wedding quilt she planned to make. Unfortunately, I'm not allowed to give a link to her post with the interesting results. I will tell you that her experiment found that Nano-Liner markers by Royal Langnickel gave the best results, with no fading and bleeding.
Another idea I love is to have the shower guests make quilt blocks for the child. The one I did for a friend was a cute fish theme. I cut background blocks, fish bodies, fish eyes, fish lips, fish fins, fish tails... you get the idea. They were all different shapes and bright colors. I backed everything with fusible web. Each guest picked the body parts for one fish and fused it onto the background block. Some people wrote good wishes or words of advice to the child on their block. I took the blocks home, added sashing, quilted it, and gave it to the parents-to-be. It turned out to be one of their most treasured gifts they received for the baby, and everyone at the shower had a lot of fun assembling their fish.
However, I'm not sure how much any of this helps you at this point. Sorry.
The only thing I can think of is to not wash the quilt. Make it a wallhanging instead.
Last edited by Peckish; 03-27-2016 at 12:59 PM.