More than a hundred children have died or been seriously injured in the last decade after squeezing through tiny pet doors and getting into swimming pools or other dangerous places, new research has found.
"What we see is a picture that's emerging which shows that the pet door is a really serious hazard in a home that no one has really had on the radar screen," said Sean Kane, of Safety Research and Strategies.
At the request of trial lawyers, Kane combed through hundreds of coroner's reports and media accounts.
"It's a very laborious task to get through the documents and the data and the connections to find these incidents," said Kane. "But I think at the end of this we're going to find hundreds of incidents."
Kane compared the issue with pet doors to the discovery of the pattern of children hurting themselves in cribs.
In a demonstration, three-year old Dylan Didier was able to easily squeeze through a pet door meant for cats and small dogs.
"Parents don't appreciate that their children, even if they're bigger, can get through," said Dylan's father, Hank Didier, a Florida lawyer suing a pet door manufacturer for the family of two-year old Matthew Ranfone.
Matthew's mother Carol, of Spring Hill, Florida, found her son floating in the backyard swimming pool after he managed to get through a small pet door in the family home.
"I remember when the accident occurred," she recalled, "and thinking to myself, 'How in the world did he ever fit out of that door?'"
The PetSafe door in the Ranfone home contained no warning to parents of the possible danger on its package or product instructions.
She was outraged to learn that many children had died under similar circumstances before her son.
"It was just unbelievable to me that all of these accidents happened as a result of doggie doors and how come I wasn't informed," she told ABC News.
The manufacturers of the PetSafe door, Radio Systems Corporation, of Knoxville, Tennessee, would not provide any executive to talk with ABC News.
In a statement, the company said its "thoughts and prayers go out to the Ranfone family," but declined further comment, citing the ongoing litigation.
Pet Door Company Says Parents at Fault
In depositions in the Ranfone case, the company's quality director, Steve Ogden, said, in effect, the parents must bear the responsibility for their son's death.
"We believe it is obvious that a dog door is an opening to the outside world in the same way a door that's opened is an opening to the outside world and we consider that the parent is responsible for supervising the child from going out this obvious opening," Ogden testified.
PetSafe does acknowledge the problem, however, on its more expensive, electronic pet door. A remote device attached to a pet's collar unlocks the door as the pet approaches. The door then locks again after the pet exits.
In its marketing materials, the company touts that the electronic lock "will prevent children from leaving the home."
"Clearly they're aware that children interacting with doors is an issue," said lawyer Didier. "They're actually trying to make money on other products by selling them as protecting children, and I think that's talking out of both sides of your mouth."
A spokesman for the pet business trade association said he welcomed the ABC News investigation and hoped it would lead pet door manufacturers to provide warnings in the future.
"I think that now that it's known to be a problem, you'll see it there," said Bob Vetere, president of the American Pet Products Association. "To me as a parent, if something happened to my kid I'd be blaming myself. But if it was a problem that I had no idea could possible occur, I'd be thinking, gee, I wish somebody had told me about it."
Carol Ranfone has started her own web site, Pet Access Dangers, to share Matthew's story with other parents, and warn them of the risks involved with pet doors.
"I'm doing it for Matthew. It's like in my mind, I can't save Matthew's life, but I can save another child and if this is my goal in life and if this is my mission in life, then I'll do it."