It's been half a century, but Françoise Ruperthouse still doesn't know what happened to two of her siblings.

"At our house, there were always two empty chairs," Ruperthouse, who grew up in the remote Algonquin community of Pikogan, north of Val-d'Or, said Tuesday at the national inquiry into murdered and missing Indigenous women and girls.

In the late 1950s, at age two or three, her brother Tony was airlifted to the hospital in Amos, Que., to be treated for a respiratory infection. The family was living in the bush, outside of Pikogan, at the time.

Tony never came home.

"There was no body; there was nothing, no certificate. We were just told, 'Your baby is dead,'" Ruperthouse told the inquiry.

But Ruperthouse later discovered, through medical records, that Tony had been transferred to the hospital in Baie-Saint-Paul, where he stayed for more than five years before he died at the age of seven.

A year or so after Tony, Ruperthouse's sister Emily, then five, was taken to the hospital in Amos to be treated for an allergic reaction to a bee sting.

Françoise Ruperthouse prepares to testify at the hearings into missing and murdered Indigenous women in Montreal. (Sarah Sanchez/Radio-Canada)

Emily wasn't seen again for 30 years, until health authorities in Baie-Saint-Paul contacted the health centre in Pikogan looking for her family. By the time she and her family were reunited, her health had deteriorated. She died in 2000.

The mystery of their disappearances has haunted her family, Ruperthouse said, and she wants answers before her 84-year-old mother, Hélène-Joséphine, dies.

"They suffered from guilt and regret," Ruperthouse said of her parents.

Similar cases across Canada

Michèle Audette, the commissioner of the inquiry, said she's heard similar stories as the inquiry has moved across the country.

Radio-Canada's investigative program Enquête detailed cases of Atikamekw children on Quebec's North Shore who were sent to the hospital by float plane without their parents.

Upon their release, some disappeared, placed with white families without their parents' consent. One of them was even declared dead when he was still very much alive.

Audette said the commission will use its powers to force both the federal and provincial governments to hand over any documentation that will shed light on the Ruperthouse family's case.

"It's fundamental, and these are questions we will ask," she said, adding that the commission will, ultimately, make recommendations to address the mistreatment of Indigenous children by Canadian health care institutions.

More coverage of the inquiry:

More than 70 people are expected to testify this week at the Bonaventure Hotel in Montreal — either in public, in private to inquiry staff or in writing.

The national hearings began in 2016 and, last week, organizers requested a two-year extension.