HILO, BIG ISLAND (HawaiiNewsNow) - "We wonder so much about where she is, what could have happened," says Kawehi Moku. Her older sister, Marlo Moku disappeared more than five years ago.
Kawehi last spoke to her sister on the phone on September 23rd, 2008. Kawehi says Marlo seemed fine. But when she didn't pick up her kids from school later that day, the family knew something was wrong.
Marlo Moku may have gone to the 7-11 on Kaumana Drive but police are unclear what happened after that.
Some have wondered if the 33-year old just ... left ... but her family says there's no way she would have abandoned her kids.
"She wouldn't have left the three of them behind, something bad must have happened to her," says her sister, "(She was) a loving mom, she always had the three of them with her."
"It is unusual for a parent, a mom, to leave behind her kids," says Lieutenant Gregory Esteban of the Hawaii Police Department's Criminal Investigations Unit.
The kids were 10, 8 and 2 years old when Marlo vanished.
Weeks later, her Chevy Corsica was found at the bottom of a cliff in Hakalau. For Kawehi, that was proof that her sister was a victim.
"Somebody's trying to hide something. The car was dumped, the license plates were ripped off, none of her belongings (was) in it," she says.
"That was her main mode of transportation," says Lt. Esteban. "The unfortunate part, the vehicle was exposed to the elements, the salt water."
Hilo Police are planning on re-testing the evidence collected to see if new technology can bring new leads. But the key to solving most cold cases, time.
"As time goes by, relationships change," says Lt. Esteban, who hopes that a witness who wouldn't or couldn't cooperate back then might be willing to now.
Marlo Moku's three kids are living with family members.
"They miss her a lot," says Kawehi, "At times I just want to break down and cry, but when I look at them... I'm the one they look up to now so I have to be strong for them."
Kawehi Moku runs a facebook page about the case https://www.facebook.com/#!/missingmarlo.moku?fref=ts