(CBS) — Rachel Mellon was thirteen years old when she simply vanished from her south suburban home. That was twenty years ago this week. The case is still considered active by police.

CBS 2’s Dana Kozlov talked to one of Mellon’s best friends about her hope for closure.

Carrie Scaglione wistfully flips through scrapbooks she made shortly after her best friend Rachel Mellon disappeared.

“We would walk around the entire town of Bolingbrook passing out flyers,” she said.

That was twenty years ago. But Scaglione has kept the books with her, hoping, someday, she’d know what happened to her 13 year old friend.

She says to her, closure would be, “knowing what happened…being able to put her soul at rest.”

Bolingbrook police and family said Mellon was home sick on January 31, 1996. Her stepdad, Vince Mellon, was home too. He told police he went out to walk their dog for half an hour and left Rachel sleeping in her room. Her mother Amy noticed her missing later.

Back then, Scaglione says she didn’t believe Rachel ran away. She still believes that now.

“I honestly don’t think that Rachel ran away,” she said.

Bolingbrook police don’t, either. They say Rachel’s case is still an open and active missing person’s case but suspect foul play. Lieutenant Larry Carter says stepdad Vince Mellon was once the main suspect.

Mellon stopped speaking about Rachel after that, but her friends have not. A plaque, by a tree they planted, is also a reminder.

“I will never give up hope,” Scaglione said.

Friends and family will hold a twenty year memorial for Rachel this Sunday at B.J. Ward School in Bolingbrook.

We attempted to contact Vince and Amy Mellon, who now live in Tennessee, with no luck