I'm not sure, but I would guess that the problem is the Swaddlebees and not the poop stain.  I had two hand-me-downs that I'm pretty sure were Swaddlebees, that simply DID NOT WORK.  It was something about the texture of the fabric I think, I don't know.  I would lanolize them to death and they would still wick right through.  My felted wool hand-made covers and other felted wool factory mades I was given worked great.  How can a company make something like that for that price and have it just not work?  I did a little searching for reviews out of curiosity and found some similar sentiments.  Also, if you got them for overnight that is a little more of a challenge.  I use two layers of thick wool for overnight and you HAVE to have enough diaper absorbency under the cover because once the diaper is filled up the pee has to go somewhere.   That's true for any diaper system. Â
 However, I don't want to second-guess your experience either.  Maybe it is the poop stain causing wicking.  I never had a stain in the middle of a cover, only on the edges where it's less likely to wick to clothes.  I would try soaking in dish soap, rinsing well several times including once with vinegar, and then re-lanolizing.  This is just an educated guess as to what might work for a stubborn stain, I never had to resort to anything other than my Biokleen laundry liquid mixed with a little lanolin. Â
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