from damninteresting.com: Sometime in the 1940s, an improbable encounter occurred at a mental institution in Maryland. Two women, each of whom was institutionalized for believing she was the Virgin Mary, chanced upon one another and engaged in conversation. They had been chatting for several minutes when the older woman introduced herself as "Mary, Mother of God."
"Why you can't be, my dear," the other patient replied, unable to conceive of such a notion. "You must be crazy. I am the Mother of God."
"I'm afraid it's you who are mixed up," the first asserted, "I am Mary."