St. Sigrada was a sister of Didon, Bishop of Poitiers 656-670. She and her brother might have been descendants of Senator Ansbertus and of Tonantius Ferreolus, who was Consul of Rome in 453.

She was the mother of St. Léger, Bishop of Autun, and St. Guérin. She was shut up in the monastery of Notre Dame de Soissons by Ebroin, who persecuted her family for their faith in Christ. Her goods were confiscated, and her son, Guérin, was stoned to death. Her other son, St. Léger, was thrown into prison, where he was subjected to cruel conditions.

She died shortly after the martyrdom of her sons.

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