A Tennessee man already serving a life sentence for killing a young woman in 1975 has been convicted of murdering a 9-year-old Girl Scout the same year.

A jury in Nashville convicted Jerome Barrett of second-degree murder Friday, The Tennessean reported. Jurors imposed a 44-year prison sentence for killing Marcia Trimble.

Virginia Trimble Ritter, Marcia's mother, said she was not concerned that the jury did not find Barrett guilty of first-degree murder.

"We only wanted the truth," she said. "I think today we got the truth, some of it anyway, at least most of it."

Marcia disappeared in February 1975. Her body was discovered weeks later, on Easter Sunday, in a garage near where she had last been seen, six boxes of Girl Scout cookies by her side.

Barrett, 62, most recently a Memphis resident, became a suspect after he was charged in 2007 with slaying Sally Des Prez, whose body was found in her apartment three weeks before Marcia's disappearance. He was convicted of first-degree murder in that case in January.