When the Sacred Family by Raffaello painting became known as the “Madonna of Divine Love”?

I was never able to find anything in writing, suggested or reason, why or when the title Sacred Family was changed. I only read on history books that the 1514 painting on canvas, viewed and described by Vasari, on his book of 1544, became the only information, and was repeated by all the historian on … Continue reading When the Sacred Family by Raffaello painting became known as the “Madonna of Divine Love”?