Her mother had at least 25 children, of which she was the 25th (her mother was 40 when she was born). She was born into a middle-class family in Siena, Italy.
She had visions of God throughout her life, and her first vision was Christ sitting on a throne when she was 5 or 6. She decided to devote her life to god when she was 7.
When she was 16, her sister, Bonaventura, died, and her parents tried to have Catherine marry Bonaventura’s widower, but Catherine refused. She cut her hair and fasted to make herself less attractive, and her parents decided to let her do what she wanted with her life.
Catherine joined the Third Order of St. Dominic after seeing a vision of him. She fasted often,