If heard through the grapevine that your close friend's nanny was looking for a new job, and you were pretty sure your friend was not aware of this and really relies on the nanny, would you tell her?

I found out in a really long windy way-- the nanny told her friend who nannies for my sister's friend, who told my sister who told me. Apparently she wants something with shorter hours, but I wouldn't want my friend to be left in a major bind. She and her husband do not have flexible schedules.