Murder charges laid in 2013 death of Ontario’s Caleb Harrison and his mother, three years earlier

The bizarre deaths of three family members in the same home over the course of four years took a large step closer toward resolution on Tuesday when police in Mississauga, Ont., announced arrests in connection to two of the deaths and a re-launched investigation into the third.

Melissa Merritt, 33, and Christopher Fattore, 36, were arrested and each charged with two counts of first-degree murder in Nova Scotia on Tuesday for the deaths of Merritt’s ex-husband, Caleb Harrison, in 2013 and his mother in 2010.

Merritt is the mother of Caleb’s two children and moved to Nova Scotia shortly after his death prompted a renewed look into the history of fatalities inside his family home on Pitch Pine Crescent in Mississauga, Ont.

Harrison was found dead inside the home on Aug. 23, 2013, His mother, Bridget Harrison, had been found dead on April 21, 2010. It was considered suspicious at the time but not determined a homicide. His father had been found dead in the home in 2009.

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Peel Regional Police cracked the case wide open on Tuesday, announcing first-degree murder arrests in the two most recent deaths and relaunching an investigation into the third.

Insp. George Koekkoek told reporters that evidence found during the investigation into Caleb's death had linked to the death of his mother three years earlier. Once police had connected the two deaths, Koekkoek said they were able to follow clues to the arrests this week.

"Our investigation into Caleb and Bridget Harrison's death also led us to open up the investigation into the sudden passing on April 21, 2009, of Mr. William Harrison," Koekkoek said on Tuesday.

"Bill Harrison, aged 65 years at the time, was found deceased in the bathroom of the home on Pitch Pine Crescent."

Merritt and Fattore were arrested on Tuesday in Halifax, where the couple had moved to about four months ago. Merrit had been married to Harrison until 2005, when they divorced. She reportedly met Fattore the same year.

A timeline behind the series of deaths is indeed tragic. William Harrison, Caleb's father, was found dead inside the home on April 21, 2009. Police believed at the time that he had simply died of natural causes.

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The death came only one month after Caleb received a jail sentence of 18 months for killing a taxi driver during a drunk driving incident in 2005.

It was also about this time that Caleb Harrison's two children, Mason and Mecaela, were reported missing. A parental abduction alert was released for Merritt and Fattore. The children were later recovered.

The Toronto Star reports that Caleb had been granted sole custody of Mason and Mecaela, although the children had been with Merritt and Fattore at the time of their arrest.

One year to the day after Bill's death, his wife Bridget was found dead in the same Mississauga home. Peel police investigated the death and said it seemed suspicious, but no conclusive evidence was found at the time; the death was not ruled a homicide.

It was not until August 23, 2013 – more than three years later – that new evidence would be found. Caleb, who was then living at the home, failed to show up for work and was later found dead. Like his mother, the cause of death appeared to be asphyxiation.

Police have not said what discovered linked the deaths of Caleb and Bridget, nor why they are now more willing to investigate Bill's death as suspicious.

Merritt and Fattore, meantime, are scheduled to be brought back to Ontario and appear in court on January 30th.

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