The disappearance of Shelley May Anderson still weighs heavy on her siblings Judy and Keith.

"It broke my heart then, and it still does today," Judy said.

"I should've went and seen her. I should've seen her and I didn't."

Anderson was 51-years-old when her siblings say she just seemed to vanish in 2009 from Cobalt, Ont.

She was only reported missing in July 2010 after the Ontario Disability Support Program asked Ontario Provincial Police why she was not cashing her social assistance cheques.

Judy was on the road during that time driving trucks across Canada.

Siblings launched their own search

Judy and Keith said their family was not in frequent contact with Anderson because she had been separated from them since the age of 13 after being sent to hospital in Timmins.

They said Anderson had fallen into a coma and suffered brain damage.

She eventually recovered and stayed in the Timmins area until she moved to Cobalt in the spring of 2009.

Judy and Keith said they organized their own search as soon as they found out Anderson was missing.

They remember making T-shirts, putting up posters and frantically driving around Cobalt's historic silver mine sites looking for a sign of their sister.

"We have no clue what we would do if we found her," Judy said.

"We just kept looking."

At one point, Judy and Keith said they were told to back off from the official police investigation.

Concerns about case

Judy said she believes investigators never took her sister's case seriously.

"Because she's a Native girl, Aboriginal and she's mentally handicapped," Anderson said.

"Back burner. Guaranteed."

Anderson's family is part of Temagami First Nation.

Judy and Keith said Anderson was trying to learn more about her culture before she went missing.

Keith said he has not lost faith in the police, but questions why so many cases involving missing and murdered Indigenous women are unresolved — including his sister's.

"A lot of information that they had is what we found on our own by doing our own investigation by going here and there and asking questions," Keith said.

"The police themselves didn't do a whole lot."

Anderson is one of seven documented cases of missing and murdered Indigenous women and girls from northeastern Ontario.

The total number across Canada is estimated to be in the thousands.

'Lost a full year of leads'

Detective Inspector Gilles Depratto is tasked with responding to the National Inquiry into Missing and Murdered Indigenous Women and Girls for the Ontario Provincial Police.

He is familiar with Anderson's case, but not in charge of it.

Depratto said there have been sightings of Anderson, but none have been confirmed.

He also said the circumstances in which Anderson disappeared present a challenge for investigators.

"I would imagine that it would've been hard because she went missing sometime in September 2009 and it wasn't reported until the summer of 2010 to the police," Depratto said.

"You've already lost a full year of leads that we could attract to try to determine her whereabouts at that time. It's always very important if someone goes missing that that person be reported as soon as possible."

Keith and Judy said they tried to keep in touch with Anderson over the years.

They have vowed to continue the search for their sister so they can reunite their family.

'Too many of them out there that are missing'

Anderson had three children, but Keith and Judy said they were taken away from their mom when they were born because of her health condition.

"We've got in touch with her children a couple of years ago. All three of them were adopted by one family, so the kids are doing well. But like us, they would like to know where their mother is," Keith said.

"Until they find her body, we can't put closure to it."

Ontario Provincial Police are still asking for tips in Anderson's case.

Judy and Keith said they still want to see more done to find Anderson, and protect Indigenous women and girls.

"There's too many of them out there that are missing," Judy said.

"It just upsets me to no end."

Tune into CBC Sudbury's Morning North at 7:20 a.m. ET during the week of October 23 to hear a new series called Unresolved, about missing and murdered Indigenous women and girls from northeastern Ontario. Listen live here.