Willow Short, 2, who was featured last year in a New York Times story about her life after her postnatal heart transplant, was among five killed in a murder-suicide in Pennsylvania this weekend. The family was the subject of many local and national news stories in the aftermath of her surgery. But Willow, and her sister, brother, and parents were all found shot to death in Berks County late Saturday, officials said, calling the event a “tragic domestic incident.” It was unclear Monday whether Mark Short or Megan Short pulled the trigger, killing the whole family and even their dog. Liana, 8, and Mark Jr., 5, were among the dead. A note found with the bodies appeared to point to a murder-suicide, officials said.