CHICAGO (CBS) — Stacy Peterson vanished more than 10-years ago under suspicious circumstances.

Her family believes she was killed by her husband, former Bolingbrook police Sgt. Drew Peterson.

Now, as CBS 2’s Mai Martinez reports, there is a possibility of charges in the case, and a renewed effort to find Stacy’s body.

Stacy Peterson’s sister, Cassandra Cales, suspects Stacy’s remains may be in the Chicago Sanitary and Ship Canal in Lockport.  Cales has spent thousands of dollars on underwater searches, including one last week.

“I have spent over $15,000 in the last two months with high tech sonar, dive teams, fuel, travel,” she said.

“I’ve never stopped looking for Stacy,” said Cales, adding she feels closer to her missing sister when she is looking for her at that location.

Cales says she was guided to the area by a search team in November, 2007–three weeks after her sister disappeared.

“They came up with the sonar image and they turned it into law-enforcement the same day that they got it and it was never looked upon my law enforcement,” Cales said.

Cales said investigators said, “it wasn’t worth looking at” and did not elaborate. Cales is certain the remains are there.

Cales said authorities did tell her late last year that they were working to charge Drew Peterson in connection with Stacy’s disappearance–even without a body. That’s why the search is so important, Cales said.

“Them charging it without a body is basically a waste of time. Drew is going to die in prison as it is,” Cales said,

Peterson is serving a 38-year sentence for murdering his third wife, Kathleen Savio. He was sentenced to another 40 years for attempting to hire somebody to kill the prosecutor in the Savio case, Will County State’s Attorney James Glasgow.

“Stacy was all I had,” Cales said. “I mean we had a rough childhood and it was just me and her together all the time. She was a mother to me because she was a little bit older.”

“She was just my everything and that was taken away from me and I am not going to let that go.”

Cales says she has another search planned and is hoping to raise $10,000 to help pay for it.

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