Jody, the poor mum must be exhausted I am sorry she hasn't found anyone to help her. It is hard to know without asking some questions, but it could be lactose overload. This is common with oversupply and what you have described fits. The good news is that it usually eases after the early weeks, and there are some things that can be done to manage it in the meantime, like spacing feeds, or block feeding (feeding from the same side for 3 hours or so before swapping sides). There is some really good information about it in the lactose intolerance article here - Australian Breastfeeding Association - Lactose intolerance and the breastfed baby.

I wish her all the very best with getting through this difficult time