Dayle Haddon, a model and actress who graced many a magazine cover in the 1970s and 1980s and bucked the fashion industry by continuing to model later in life, was found dead at her daughter’s home in Bucks County, Pennsylvania, on Friday morning. She was 76.

The cause of her death was believed to be carbon monoxide poisoning, the authorities said. Emergency personnel discovered Haddon’s body around 6.30am in a bedroom on the second floor of the house, and also found a man passed out on the first floor of the home, according to a statement from the Solebury Township police department.

High levels of carbon monoxide were detected at the property, and three emergency responders were treated for carbon monoxide exposure. A faulty flue and exhaust pipe on a gas heating system is believed to have caused the carbon monoxide leak, the authorities said.

Walter Blucas, 76, the man who had passed out, was transported to Robert Wood Johnson University Hospital and was in critical condition on Saturday, according to local authorities and Haddon’s daughter, Ryan. Blucas is Ryan’s father-in-law.

Haddon’s life is a winding tale of reinvention and creativity, as her daughter recalled in a phone interview on Saturday evening. Her adventure began in Montreal, where she started to train at age 5 in rigorous dance rehearsals.

Haddon took on modelling to pay for her classes. When she was discovered by the legendary fashion agent Eileen Ford, Haddon had to make a choice between the stage and the catwalk. She moved to New York and lived in Ford’s home to begin her modelling career.

Born on May 26, 1948, Dayle Pauline Haddon was a leading female model of the 1960s and through the early 1980s.