The family of Hillary Wilson, 18, is preparing for a somber anniversary with Aug. 20 marking one year since her body was found. The case remains unsolved.

"I know whoever hit her, hit her really hard and there were a lot of bruises on her," said Gwen Wilson, Hillary's mother.

Hillary was last seen alive standing by a payphone near McKenzie Street and Selkirk Avenue.

Her body was discovered in a field near the north Perimeter Highway and Lagimodiere Boulevard.

Wilson's mother believes people know what went wrong that night but are not coming forward.

"I'd like her friends to be honest with police and not to hide anything. They should tell the truth," said Gwen Wilson.

The family is still struggling to deal with the death.

Hillary's body was found on the same day as her brother Dino's birthday.

"I think about her each and every day," said Dino Wilson.

"I know sometimes that her spirit is here. I sense it a lot," said Gwen Wilson.

The family has been putting up posters along Selkirk Avenue and McKenzie Street, in the area where Hillary was last seen alive.

Every time they put up posters, however, someone tears them down.

"We are trying to find out who did this to Hillary and all our efforts are in vain because someone keeps ruining it," said Gwen Wilson.

The family is planning to hold a memorial walk for Hillary on Friday. It begins at 5:30 p.m. at McKenzie Street and Selkirk Avenue and ends at the legislative building with a candle-light vigil.

The RCMP serious and major crime units continue to investigate her death.

Officers ask anyone with information to contact Crime Stoppers at 1-800-222-8477.

- with a report from CTV's Stacey Ashley