At age 12 or 13 Agnes was ordered to sacrifice to pagan gods and lose her virginity by rape. She was taken to a Roman temple to Minerva (Athena), and when led to the altar, she made the Sign of the Cross. She was threatened, then tortured when she refused to turn against God. Several young men presented themselves, offering to marry her, whether from lust or pity is not known. She said that to do so would be an insult to her heavenly Spouse, that she would keep her consecrated virginity intact, accept death, and see Christ. Martyr. Mentioned in first Eucharistic prayer. On her feast day two lambs are blessed at her church in Rome, Italy and then their wool is woven into the palliums (bands of white wool) which the pope confers on archbishops as symbol of their jurisdiction.
The Pallium (derived from the Roman pallium or palla, a woollen cloak) is an ecclesiastical vestment in the Roman Catholic Church, originally peculiar to the Pope, but for many centuries bestowed by him on metropolitans and primates as a symbol of the jurisdiction delegated to them by the Holy See. In that context it has always remained unambiguously connected to the papacy.
I've found stuff on the web indicating that it's St. Anthony the Abbot, but it's unclear whether it is simply legend, and not doctrine.
St. Francis of Assisi does not count, here. I'm looking for a specific. The Vatican holds (or used to hold) an annual ceremony where livestock is blessed in St. Peter's Square.