Family members of a teenage girl who died under mysterious circumstances in March say they're concerned about the rumoured travel plans of a convicted sex offender connected to the case.

Sixteen-year-old Kayla LaLonde was found dead in Burnaby on March 2, the same day her friend Martha Hernandez died in a Richmond home. Police say both girls were killed by a lethal mix of drugs and alcohol.

Hernandez died inside a home rented by Martin Tremblay, a man with five previous convictions of sexual assault against young girls. LaLonde had been at the same home earlier that night.

LaLonde's stepfather Grant Petrygan told CTV News he's heard that Tremblay is planning to leave the province -- a rumour Tremblay's Richmond roommates confirmed.

"This man is now doing a garage sale…and moving to Montreal. He's going to be back east and now people back east will be oblivious to what has happened here," Petrygan said.

Tremblay would not talk about his plans when CTV News caught up with him in Richmond.

Kayla's parents still want to know how she got to Burnaby from Tremblay's house, and why she had bruises all over her shoulders.

"She got dumped off and dropped off there," Petrygan said. "The police came to us and saw us once and they haven't seen us in three months -- not even a courtesy call to say, ‘We're still looking into it.'"

Kayla's mother Angela LaLonde says she's also frustrated with the silence from the police.

"What they told me was, ‘Angela, we're very close to an arrest,'" she said. "That was the last time I saw them, last time they even said anything, and I've tried calling and tried calling and they will not call me back."

Calls from CTV News to the lead police investigator and the Richmond RCMP's spokesperson were not returned.

Since LaLonde and Hernandez died, young women who knew Tremblay have spoken to CTV News, concerned that he may have been involved in the deaths.

Tremblay went to jail for drugging and sexually assaulting teenage girls in 2003.

After the two girls died, Tremblay fled to Pender Island. When CTV News caught up to him there, he said that police had already questioned and released him.

Angela LaLonde says she's worried about what could happen if Tremblay moves to a new community and parents there aren't aware of his history.

"I wish I knew his full name at the time so I could have looked him up. I would have had my daughter out of that house and every other kid that I saw there."

She's now launched a Facebook campaign to raise money for a heart-shaped gravestone for her daughter.

With a report from CTV British Columbia's Lisa Rossington