The parents were in bed watching TV with their newborn son and dog Thursday night when the mother coughed. The coughing startled the dog and it unexpectedly bit the baby, Sgt. Tu Nguyen said.
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He said the parents pulled the animal off and took their only child to the hospital, where he was pronounced dead.
"At this time, we're looking at this as nothing more than a tragic incident," said Nguyen, a member of the child abuse unit.
An autopsy is underway to determine the cause of death.
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Animal control officers took the 2-year-old dog, a neutered male American Staffordshire terrier-mix named Polo, into custody, said Dan DeSousa, deputy director of the county Department of Animal Services. The dog will be held in quarantine for 10 days to determine whether it has rabies.
It will be up to the owners to decide whether to reclaim the dog, DeSousa said.
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