Baking soda worked!!!!! I put the block in the sink and soaked it. Then I sprinkled the baking soda all over the stain and just let it sit for a bit. When i went back in I gently rubbed it in and added a bit more water and let it sit some more. Then i added the vinegar...the kids loved that part! Once I was done rinsing the stain was gone! I am SO glad I asked here first before trying anything else! I'm going to use some interfacing on this block since the edges are so frayed. The other one that was fragile like this one helf up pretty well to quilting but the edges had be be sewn over in several places.