Saint Marguerite d'Youville was a Canadian nun and the founder of the Grey Nuns, a religious community dedicated to serving the poor and sick. Born on October 15, 1701, in Varennes, Quebec, she faced many hardships, including the loss of her husband and financial struggles. Despite these challenges, she devoted her life to helping others. She is known for her compassionate work in establishing hospitals and caring for the marginalized in society. Canonized as a saint by the Catholic Church in 1990, her feast day is celebrated on December 23, honoring her legacy of charity and service.