Here is a little something I found on plastic.com this morning….the whole article appeared in the NY Times

‘The surprising result to us was that if the father was alive or dead didn’t matter. If the grandmother dies, you notice it; if the father does, you don’t.’ ‘There’s a new mystery which has flummoxed biologists and anthropologists: grannies. It seems these researchers have been blown away by the discovery that the presence of maternal grannies offers an unexpectedly potent boon on the lives of their grand kids. Consider the positive influence of grannies in rural Gambia: ‘The anthropologists found that for Gambian toddlers, weaned from the protective balm of breast milk but not yet possessing strength and immune vigor of their own, the presence of a grandmother cut their chances of dying in half.’

‘Interestingly, paternal grannies instead have a neutral or even negative influence on their grand kids. Researchers working on Japan found that ‘when a maternal grandmother lived in the household, boys were 52 percent less likely to die in childhood than if there was no grandmother present. Conversely, when the father’s mother lived in the house, boys were 62 percent more likely to die than were those without a resident grandma.’ But how do grandmas work their potent powers? Alas, the frustrated researchers have no clue. Clearly the grannies are doing something; exactly what this is is anybody’s guess.’