However, Antonio was born to a Florence still very much in the grip of February. He came into the world on a Thursday evening at 9:25 pm, (recorded as 3 and 5/12 hours past sunset). Of all the days to be born, 29 February was considered among the least auspicious. A dire Northern Italian folk proverb states "An bisesti, o la mama o 'l bambi", predicting that when a child is born on this day, by the end of the year either the infant or its mother will die. Indeed, the Italian word naming the day, bisestile, had become a synonym for misfortune or calamity, as is still the case for the French cognate bissêtre. Whatever stock the family put into ancient superstitions, happily this prophesy did not come true for Dianora or her fourth child Antonio.
The baptistery record for Antonio Neri reads:
Thursday, 1 March 1575: Antonio Lodovico was born to Mr. Neri Jacopo and Dianora di Francesco Parenti, residents of San Pier Maggiore parish. The time of birth was 29 February, at 3 hours 25 minutes past sunset. The godparents are Francesco di Girolamo Lenzoni, and Ginevra di Federigo Sassetti.