The FSSP Daily Missive today has an illustrated account of the long established devotions to Our Lady and to an icon of her, which are held each year on this day in Cerami in Sicily.
As with so many of these popular devotions the icon has a history that conforms to a type, the loss and miraculous recovery of the wonder working image. Such stories may not be in themselves untrue but some of the actual history has perhaps been lost along the way. Nonetheless this is a genuine tradition and may indeed preserve traditions anterior to the seventeenth century - the point the author makes about the red dresses of the girls escorting the image. Such occasions have survived in Mediterranean Europe whereas they have virtually disappeared in the culturally cooler climes of the north, where comparable events certainly did once take place.
The article can be seen at Maria SS. della Lavina: Torrents of Water and Drops of Milk
The Clever Boy would add that he endorses Fr Rock’s point about depictions of Our Lady suckling the Christ Child, and how Reformation and Counter-Reformation scruples and sensitivities moved against it. By contrast late fourteenth century glass ( now replaced by a copy ) in the east window of the chapel of William of Wykeham’s Winchester College, shows Our Lady unashamedly suckling the Holy Child. There are also late medieval paintings of Our Lady bestowing her milk upon St Bernard. A more robust age.