A 24-day-old boy was in critical but stable condition a day after receiving the heart of an infant girl, officials at Loma Linda University Medical Center said. Trevor Reed, who had a usually fatal heart defect, was recovering in the intensive-care unit of the medical center, said hospital spokeswoman Anita Rockwell. The boy was born Sept. 3 to John and Sherri Reed of the Sacramento area and had hypoplastic left heart syndrome. He received the heart of a baby girl born with fatal defects Friday in Knoxville, Tenn., said Marty Walker, coordinator of the Knoxville Organ Donor Program. Dr. Leonard Bailey, who has performed all six of the infant-to-infant heart transplant operations at the San Bernardino County medical center, performed the surgery.