The man found guilty of murdering Sabrina Patterson wants to appeal his conviction.

“I think they’re grasping at straws, trying to find a way to appeal it,” says Denise Murphy, the victim’s sister. “He’s got nothing but time in there right now. He’s probably just twiddling his thumbs trying to come up with some way to get out.”

Fred Prosser, 33, launched his appeal through lawyer James Matheson.

Prosser contends his first-degree murder conviction was a miscarriage of justice. The Court of Appeals could acquit Prosser or order a new trial.

Patterson’s family says the move only adds insult to her death.

“I think justice was served. I think it was a fair trial,” says Dale Patterson, the victim’s brother.

The 25-year-old mother of two was last seen on Oct. 29, 2010. She was reported missing two days later – the same day Prosser disappeared.

Her body was found in the woods near the Prosser home in Shenstone, N.B. on Nov. 4.

After one mistrial, a jury found Prosser guilty of first-degree murder, sexual assault and sexual assault causing bodily harm.

Prosser was immediately sentenced to life in prison.

“After the verdict, we figured it was all done and over with and hopefully put it behind us and move on,” says Dale Patterson. “It would be nice to have that closure there, not have to go through that each and every day, and have it thrown in our faces.”

Murphy says she hasn’t yet spoken with the Crown about the appeal but plans to contact Annie St. Jacques in the near future.

For now, the Patterson family will continue to prepare for a fundraising marathon in support of Crossroads for Women.

“To me, it’s going to make us work even harder because we know the appeal could be coming up right around the same time, so we’re going to focus on the good rather than focus on the negative of a possible appeal,” says Murphy.

Prosser faces six other charges involving Patterson, related to incidents that allegedly took place in the months leading up to her murder.

His appeal could be heard as early as this spring.

With files from CTV Atlantic's Jonathan MacInnis