I have always been a washer...and STILL had a big problem. I made a quilt for my son. Mostly WOW and creams. All prewashed. After it was done, i decided to wash the WHOLE quilt. Well, I'm glad its for my son..and it was ME that washed it!
The one on the left is before as it was being quilted. The one on the right is after. The blue from the border (I THINK) only dumped on certain fabrics. 2 in the cream rows and one in the white. DS thinks it looks like it was on purpose. I learned a valuable lesson! EVEN if you prewash? If the color catcher comes out DARK BLUE, wash it AGAIN! As always JMHO.