Katrina Monica Willemsen Brockville

Family members have identified Katrina (left) and Monica Willemsen (right) as the girl, 5, and mother, 36, found dead in Brockville Thursday in a suspected murder-suicide. (Facebook)

A murder-suicide is suspected after a mother and her five-year-old daughter were found dead in their Brockville, Ont., apartment on Thursday.

Family and neighbours have identified the mother as Monica Willemsen, 36, and the daughter as Katrina.

The girl's school called police when she was absent from class without warning on Thursday morning, Brockville police said.

Police found the girl dead, along with her mother, in their apartment at 845 Kyle Court that afternoon. 

The Upper Canada School Board has grief counsellors on hand at the girl's school, police said.

"Family members are devastated by these tragic events and are seeking privacy," police said in a news release.

Neighbours, family say no warning signs

Neighbours said they didn't suspect anything was wrong when they would see the two of them around.

"She wasn't mean or rude or anything to the little girl. She walked her to school every day," said Dale Cheetham.

"I'd met her at the bus stop a few times, her daughter was very sweet," said Chris Hanna. "It's quite upsetting."

Two stuffed ducks, flowers and a sign saying "You will be missed but never forgotten" had been left on a bench near the apartment on Friday.

One member of the victims' family told CBC News that Monica had suffered from depression in the past but there were no signs anything like this would have been coming.

The causes of death have not been released, and police said they are still trying to determine when the girl and her mother died.

"We're looking into everything, this is completely unexpected... there were no indicators to us that anything would happen, nor were there any to the family or anyone else," said Brockville Police Chief Scott Fraser.

"It's a tragic event and it's really unfortunate."

The coroner’s office is helping police with the investigation.

Brockville is 115 kilometres south of Ottawa.