Try a cup of kosher salt in the wash...works for me., Learned this trick years ago from a home ec teacher. Just had the opportunity to use it last night...I made a red and white quilt...prewashed it, made the quilt, gave it to DD. then some time later used the same fabric to make a valentines mug rug and it bled when i ironed it...she called last night and said GS peed on the quilt and how to wash it....I feared the worse and told her chances were good it would turn pink. But she used the salt, then gave it an extra rinse and it came out great.