It seems to me I remember reading years ago, either in an anthropology course or articles in National Geographic, about an indigenous population somewhere where the grandfathers breastfed the babies.  I think I remember an actual picture of a grandfather with saggy longish breasts, and a baby on one of them. 

Those of you who have extensive background in anthro, did I dream it up?
Was it just a very vivid "bubbeh meiseh" (old wives' tale?)

  Chanita, San Francisco, once again an enqiring mind.