Anna dei Celli, the widowed mother of Gregory dei Celli, of Verucchio, Italy, prayed to Saint Monica and her son Saint Augustine for spiritual assistance in raising her own son. When Gregory was fifteen, he and his mother dedicated themselves to Saints Augustine and Monica respectively. Anna built an Augustinian monastery for Gregory to enter, while Anna took a small cell for herself at this same monastery, where she spent the remaining ten years of her life. As a religious of exceptional holiness, Gregory obtained the return to the faith of many who had fallen into heresy. Following Anna's death, Gregory's fellow monks turned against him and expelled him from the monastery. The twenty-five-year-old monk eventually found refuge with the Franciscans of Monte Carnerio, where he spent the rest of his life as a hermit. He is said to have lived to the age of 118. The intercession of Gregory has been invoked for the intention of obtaining rain.
