S&P Global Ratings affirmed its 'AA' long-term rating on bonds issued by the Massachusetts Development Finance Agency for Children?s Hospital of Boston (Children's) and on Children's taxable bonds. The outlook is stable. Securing the bonds is a general obligation from the obligated group--of which Children's is the only member--as well as a guarantee from its parent, Children's Medical Center. Nonobligated entities include employed Harvard Medical School and Children's physicians and various support companies, primarily holding real estate. The rating reflects our view of Children's healthy balance sheet including robust unrestricted reserves, light debt levels, and excellent fund-raising capabilities that consistently and materially contribute to cash flow. Children's operating margins have historically been positive and reliable based on strong demand for