Ontario Provincial Police have been asked to expand their investigation into a nurse accused of killing eight elderly patients after two more families expressed concern about the "unexpected" deaths of relatives who lived at a facility where Elizabeth Wettlaufer worked, a London, Ont., lawyer says.

Wettlaufer, 49, is facing eight counts of first-degree murder charges in connection with deaths that occurred at Ontario nursing homes between 2007 and 2014.

Relatives of the two patients have turned to London lawyer William Brennan for assistance in making sure the cases are thoroughly examined by the OPP. Brennan told CBC Toronto the families "know that Wettlaufer was working at the nursing home at the time their loved ones died."

He said they want the OPP to find out what, if any, direct access Wettlaufer had to their loved ones.

"Obviously, everyone in a nursing home has some health issues but their individuals had nothing that was expected to cause their death imminently. They were unexpected deaths," Brennan said.

Wettlaufer, who was arrested in October, made a brief appearance in court Thursday and her case was put over to the new year.

Arpad Horvath, 75, was the lone alleged victim to die at London's Meadow Park facility. The seven other patients were allegedly killed at a Caressant Care facility in Woodstock, where Wettlaufer had also worked as a nurse.

Police had no idea the deaths were possible homicides until Wettlaufer sought treatment at Toronto's Centre for Addiction and Mental Health in September and allegedly provided the information to staff.

Before any charges were laid, investigators obtained a peace bond preventing Wettlaufer from going to any long-term care facilities or retirement homes. The court order also barred her from possessing any drugs, including insulin, except those prescribed to her for her own care.

Police have said all eight patients died after being injected with a substance.

Investigation ongoing

Brennan says while police are looking into the deaths of the two other patients, he expects answers won't come quickly.

"Obviously, there's a lot of police work to go on in this case. There's eight first-degree murder investigations ongoing, so I'm not surprised it could take some time before they start to investigate other deaths."

London, Ont. lawyer William Brennan says his clients 'know that Wettlaufer was working at the nursing home at the time their loved ones died.' The nursing home declined to comment. (Joe Da Ponte)

OPP spokesperson Dave Rektor told CBC News: "We urge anyone with information to contact investigators."

He also didn't rule out more charges.

"The investigation is ongoing and at this point we are not able to comment further on any aspects of the ongoing portion of this investigation. We will continue to follow the evidence, take it to where it leads and if warranted, lay charges as we would in any investigation."

London's Meadow Park facility did not reply to a request from CBC News for comment.

"My understanding is that Meadow Park is co-operating fully with police right now, and obviously, as the police investigation is ongoing, information is at a premium," Brennan said.

Wettlaufer has not yet entered a plea on the charges. It's expected police will be in a position to provide her lawyer with more details about their investigation by the end of January. Wettlaufer is currently awaiting trial at the Vanier Centre for Women, a jail in Milton.

John Lancaster can be reached at 416-205-7538 or at john.lancaster@cbc.ca