Children's Hospital of Philadelphia apologized Wednesday for the way it had communicated with the parents of Amelia Rivera, the 3-year-old disabled girl whose parents want her to have a kidney transplant. In a statement released with the approval of the Riveras, the hospital expressed regret for how it had handled the situation. Joe and Chrissy Rivera gained national attention in January when they said a hospital physician had recommended against such a transplant because of her mental disability.