is the mom using bags for freezing???  If so,have her check the smell of
the bags BEFORE using,as vinyl and other products often have an odor when
improperly packaged.  Haven't you noticed this even with glad bags that
food tastes of the odors from the bags being packaged prior to proper
cooling. I once called the manufacturer of such bags regarding the
smell/taste and was told to return them to the store for the above reason
on improper packaging.     Using the herb goldenseal also causes a smelly
milk.Denise Ferrell