VICTORIA - Hope is a ringing telephone or a passing police car for Crystal and Bruce Dunahee.

The next phone call or visit from the police could bring home their son. Or it could give them the answer to the question that has caused them untold agony and grief for the last 20 years: what happened to Michael?

The Dunahees have been clinging to hope for 20 years waiting for word about their son, who was four years old when he disappeared from a Victoria sports field that March day two decades ago.

"We hope for that one tip, (from) somebody that knows what happened on March 24, 1991. We want that person to come forward and tell us so that we can put an end to this chapter in our life and move on," Crystal Dunahee said Wednesday.

Police say they continue to receive tips and continue to investigate each one. Just last month, they gathered DNA from a young man living in Chase, B.C., who many in the community believed looked like a grown-up Michael Dunahee.

But police said the DNA evidence ruled out the young man, who they say did bear a striking resemblance to Michael, who would now be 24 years old.

The Dunahees spoke to media hoping to jog memories, shake loose tips and remind Canadians to keep watch on their kids. They plan to attend church on Thursday, the anniversary of Michael's disappearance.

"I wouldn't wish this on anybody," said Bruce Dunahee. "Twenty years is way too long."

Michael vanished while Crystal Dunahee was playing a flag football game and Bruce was getting ready to watch from the sidelines.

"I believe somebody took him," said Bruce. "For what reason, we don't know. We just want our son back."

Victoria Police over the years they have received 10,000 tips, and they still have an active investigation.

Deputy Chief John Ducker said the disappearance haunts the department, individual officers and the Dunahee family, which includes a sister who was just a baby when Michael vanished.

It has remained one of the city's darkest unsolved crimes, he said, one that he has lost sleep over since he was a junior investigator two decades ago. Ducker recalled the massive police investigation that had him working 15 days straight, with no clues.

"I've never seen an effort like that in my history in policing," said Ducker. "That was a very frustrating part of it. We didn't get that one piece of information we needed to go the distance on it."

Sgt. Grant Hamilton said the recent DNA investigation that led police to the B.C. Interior shows that police will never given up on the case.

"The Chase community was quite insistent the boy was Michael, and with his consent a DNA sample was obtained as recently as late February 2011," he said.

Crystal Dunahee said she's had her hopes raised and dashed on several occasions, but she now tries to rely on her senses about her son.

"They do their DNA's, and I say, 'show me a picture and I'll tell you,'" she said. "They did have one like that (Chase) one, another one case of similarity (to Michael), and they were adamant that this was Michael, and I said, 'No. Don't waste your time.'"

Hamilton said the case is not closed. There is still a $100,000 reward for information leading to information about Michael's whereabouts.

"It's an open and active investigation," said Hamilton. "Our goal is to bring Michael home."

He said he hopes publicity around the 20th anniversary could shake loose more tips, and Crystal Dunahee said she, too, wants to keep her son's plight in the public eye in case it prompts a lead or tip that leads to his discovery.

"I don't know how we get by," she said. "It's just a matter of instinct. You don't give up. You continue going forward until you have the right answer."

Anyone with information about Michael's disappearance should call the Victoria police tip line at 250-995-7444 or CrimeStoppers at 1-800-222-TIPS (8477).