A Hamilton mother has been charged with manslaughter after allegedly poisoning her four-year-old son in 2017.

Investigators say Kane Driscoll dealt with a litany of medical issues throughout his life, but his health was starting to improve before he died.

His mother, 39-year-old Lisa Strickland, appeared in Ontario provincial court in Hamilton on Friday.

"We have a child who should be six years old now, going to school and living a normal life, whose life was unfortunately cut short," Hamilton police Det.-Sgt. Peter Thom told reporters at a Friday morning news conference.

The investigation started in September 2017 when police received a call about an unresponsive child at a home on Idlewood Drive on the Mountain.

Emergency crews got there and found the boy "obviously deceased." The police major crime unit automatically investigates the death of any child under five years old, so they started examining the scene.

There's no reason that child should have the narcotic that have the fatal dose in it. It should not have been in his system. - Det.-Sgt. Peter Thom

At the time, officers found no signs of foul play, and the boy's parents were co-operating with investigators.

In a news release, police said Kane was born with several medical issues that resulted in major operations and months in hospital.

"He seemed to be out of the worst of it. He started [junior kindergarten] at a local school, and he was starting to live a normal four-year-old's life," Thom said.

"He was to continue seeing doctors, but as far as his life expectancy, he was expected to live a fairly normal life."

Police say Kane was born with a number of defects and genetic issues. (Facebook)

A post-mortem found no anatomical causes of death, but toxicology tests were ordered. Police said they were told in December 2017 that those tests found a lethal dose of a "prescribed narcotic" in the child's system. Thom would not specify what the drug was or if it was prescribed to either of his parents.

"There's no reason that child should have the narcotic that had the fatal dose in it. It should not have been in his system," Thom said.

Death ruled a homicide

Investigators said it was determined the cause of death was drug poisoning and Kane's death was then ruled a homicide.

They did not tell the public about it until now, citing "strategic and investigative purposes."

"Because of the suspects, and because of the nature of the death and how it all unfolded, there was no real threat to anyone else," Thom said.

Kane's parents were notified about his cause of death on Feb. 6, 2018, and told they were suspects. Police said both parents then got legal advice and stopped co-operating with investigators.

Strickland appeared in Ontario provincial court in Hamilton on Friday. (Facebook)

Officers started interviewing witnesses and trying to determine where the drug that killed the child had come from, they said. Officers filed and executed 48 judicial authorizations — mostly focused on medical records for Kane and his parents.

Those documents were reviewed by medical specialists, according to police, who said their investigation formed reasonable grounds to charge Strickland with manslaughter.

Kane's father is also considered a suspect, Thom said.

"At the moment we've charged the mother," he said. "The father has not co-operated since being identified as a suspect. We have further investigation to do, but at the moment it's the mother that has been charged."

Police also noted that during their investigation, they discovered Strickland was pregnant.

Strickland gave birth in N.L.

Police said they took steps to ensure the expected child's safety, which included ensuring that area hospitals alerted police when Strickland gave birth.

But police said that in October 2018, they learned Strickland had flown to Newfoundland and Labrador because she was aware of what investigators were doing. The baby was then delivered in that province.

An online obituary announced Kane's death on Sept. 27, 2017. (Arbor Memorial)

Strickland's family is originally from Bonavista, N.L., which is a small town of around 3,500 people about three hours north of St. John's. Thom said Strickland has lived most of her adult life in the Hamilton area.

Police said steps were taken in Newfoundland and Labrador to protect that child, who remains on the East Coast. The child's father is still in Ontario, Thom said.

Officers with Hamilton's major crime unit travelled to Bonavista with an arrest warrant on Feb. 6, 2019, and, with the assistance of the St. John's RCMP Major Crime Unit, arrested Strickland for manslaughter.

She made a brief court appearance there, and police said she returned to Ontario on Thursday and appeared at the John Sopinka Court House on Friday morning. She was remanded into custody.

Police confirmed Friday afternoon that Strickland has four other children, who are all currently living with their father; not the same man involved in the current case.

Friends say Strickland was working as a nurse in Ontario.

Strickland is originally from Bonavista, N.L. (CBC)

She continued to post about Kane on her Facebook page, even after being told she was a suspect in the investigation into his death.

In late November, Strickland shared an older photo of her son as an infant with the caption, "Miss this little boy more then [sic] words can say!"

Her Facebook page was flooded with angry comments about her son's death almost immediately after police announced her arrest.

Police said Kane's death brings the total number of homicides in Hamilton for 2017 to 11.

adam.carter@cbc.ca