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MIAMI (CBSMiami/AP) — A Delray Beach man, whose newlywed wife went missing at sea, will have to wait a bit longer to find out the length of his prison sentence.

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Lewis Bennett, 41, pleaded guilty to a federal involuntary manslaughter charge in the May 2017 disappearance of Isabella Hellmann.

On Tuesday he was supposed to have a sentencing hearing but it was delayed due to a family dispute.

U.S. District Judge Federico Moreno said he needs more information about visitation rights and creation of a trust fund for the couple’s young child. Sentencing was reset for May 28. He faces a maximum eight-year prison sentence.

Bennett, a mining engineer with dual British and Australian citizenship, told the FBI that he and Hellmann, a real estate agent, took their 37-foot catamaran, Surf Into Summer, for a belated honeymoon Caribbean cruise in May 2017 after they had been married three months. They left their infant daughter, Emelia, with her family.

Lewis Bennett (Handout)

According to Bennett on May 15th he woke in the middle of the night when the boat, about 70 miles southeast of Key West, struck something and began to take on water.

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When the Coast Guard found him on a life raft three hours later, he told rescuers he had left Hellmann on deck when he went to bed for the night in their cabin. He said when he was jolted awake Hellmann was gone and his attempts to find her failed. He said the catamaran was sinking, so he abandoned it.

It was a story he repeated to the FBI and journalists.

Investigators long doubted Bennett’s story. The FBI said an inspection of the catamaran before it sank showed portholes below the waterline had been opened and damage to the twin hulls appeared to have been caused from the inside. Also, investigators found Bennett on the life raft with $100,000 worth of coins stolen from a yacht he had worked aboard in 2016.

Bennett was originally charged with second-degree murder but made a deal with prosecutors for the lesser manslaughter charge. Moreno said at the hearing that murder would have been difficult to prove, with no body and no witnesses.

Some of Hellmann’s family members said in court Tuesday they felt Bennett was getting away with deliberately killing his wife.

“He’s not paying enough for what he did,” said one of her sisters, Dayana Hellmann Rodriguez. “I know he did something to my sister.”

In a brief statement, Bennett apologized for Hellman’s death and said is sole purpose now is playing a role in the life of their daughter, 2-year-old Emelia.

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(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)