Dayle Haddon has died from suspected carbon monoxide poisoning at the home of her son-in-law, Buffy actor Marc Blucas.

More than 400 Americans die from accidental carbon monoxide poisoning every year, which sends another 100,000 to the emergency room, according to the U.S. Centers for Disease Control and Prevention.

Authorities in Bucks County found Haddon, 76, dead in a second-floor bedroom Friday morning after emergency dispatchers were notified about a person unconscious at the Solebury Township home. A