Heather Eisenhauer and Janice Sampson say the man who killed their sons should stay in prison for life. (CBC)

After four excruciating years, the mothers of slaying victims Adam Eisenhauer and Tyler Sampson finally heard the word they wanted to hear: guilty.

Michael Joseph Mitchelmore pleaded guilty Friday to two counts of second-degree murder, as his trial was set to begin in Nova Scotia Supreme Court in Halifax.

"It's a relief we don't have to go to trial. We knew he did it," Janice Sampson told reporters outside court.

"We can eventually just think about our sons and grieve our sons, which we've been unable to do for four years, two months and two days," said Heather Eisenhauer.

Both women said they wake up every day thinking of their sons. They said the two young men were lifelong friends who always did everything they could to help each other.

The bodies of Eisenhauer, 26, and Sampson, 25, were found on Aug. 14, 2005.

Sampson died on the way to the hospital after he was found outside Eisenhauer's house in Glen Haven, a small community about 40 kilometres west of Halifax. Eisenhauer, who was partially paralyzed from a car accident, was later found dead inside his home.

Mitchelmore, of Glen Haven, was originally charged with two counts of first-degree murder.

The details of the crimes will be revealed on Nov. 24 when Mitchelmore is sentenced.

Since second-degree murder convictions carry an automatic life sentence, it will be up to Justice Kevin Coady to decide when Mitchelmore will be eligible for parole.

The two women said police told them there was no apparent motive for the murders. They want Mitchelmore to stay in prison for the rest of his life.

"As mothers there's no court on this earth that can give us justice or bring us back our happiness. But it would be nice to see other people protected," said Sampson.