Ascension Health will provide Caritas Christi with $100 million in funding, raising the possibility that Ascension could eventually take over the six-hospital chain owned by the Archdiocese of Boston. St. Louis-based Ascension agreed to buy $100 million in low-interest bonds from Caritas Christi to help shore up Caritas Christi's finances and improve its network of hospitals, which include St. Elizabeth's Medical Center and Carney Hospital. Caritas Christi is New England's second-largest hospital system behind Partners HealthCare.