Aunts of St. Gregory the Great, virgins in the sixth century, given in the Roman Martyrology, the former on 24 December, the latter on 5 January. St. Gregory (Hom. XXXVIII, 15, on the Gospel of St. Matthew, and Lib. Dial., IV, 16) relates that his father, the Senator Gordian, had three sisters who vowed themselves to God and led a life of virginity, fasting, and prayer in their own home on the Clivus Scauri in Rome. They were Trasilla (Tarsilla, Tharsilla, Thrasilla), Emiliana, and Gordiana. Gordiana, led on at first by the words and example of her sisters, did not persevere but returned to the vanities of the world. After many years in the service of God, St. Felix III, an ancestor, appeared to Trasilla and bade her enter her abode of glory. On the eve of Christmas she died, seeing Jesus beckoning. A few days later she appeared to Emiliana, who had followed well in her footsteps, and invited her to the celebration of Epiphany in heaven. Tradition says that their relics and those of their mother, St. Silvia, are in the Oratory of St. Andrew on the Celian Hill.
FRANCES MERSHMAN (Catholic Encyclopedia)