NASHVILLE, Tenn. -- One of Nashville's most frustrating unsolved mysteries could finally be over.

Video: Mother Hopes For Close In Case Of Slain Daughter

Girl Scout Marcia Trimble was slain 32 years ago while out delivering cookies, according to police.

This week, a new person emerged that has her family second-guessing all of their old theories.

Trimble was last seen by a Green Hills neighbor standing by a hedge with two people in 1975.

Since then, the strongest theory has been that Trimble was slain by two people she probably knew.

But this week’s arrest of James Barrett has brought his name into the fold with possible ties.

“If it was this man, he was 26. Marcia is not going into the garage with somebody she didn’t know unless there was a child with him that she knew,” said Marcia’s mother, Virginia Trimble.

Trimble said she is never far from thoughts of her daughter's slaying.

“Oh, it’s with me all the time. It just, you know, I have a job, and I have a family and other things to occupy my mind, but this is always in the back of my mind. She is always very close to me, very close to my heart,” she said.

She said she can't help but wonder how Barrett fits in.

In 1975, he was convicted of the rape of a Belmont student and is charged in the 1975 slaying of Vanderbilt student Sarah Des Prez. Des Prez was found dead in her apartment by her father and brother. Her father was a well-known Vanderbilt professor.

Barrett was a part-time landscaper, and his job could have put him in any neighborhood at any time in Nashville. With two outstanding DNA samples collected in 2001, there could definitely be an answer.

“If he did kill Marcia, you know, I would like to see him. I would like to speak with him and get some truth,” she said.

“Because you’ve had 30 years of speculation?” reporter Dennis Ferrier asked her.

“And in a sense, I’m not free from that, you know. To know the truth, the truth will set you free, and I would like to be free of this not knowing,” she said.

Barrett is in custody in Dez Prez’s slaying.