A man whose wife disappeared while they honeymooned at sea is facing a prison sentence after pleading guilty in Florida to a federal involuntary manslaughter charge.

A sentencing hearing is scheduled Tuesday in Miami federal court for 41-year-old Lewis Bennett. The plea agreement caps his potential prison sentence at 8 years.

Isabella Hellman went missing as the couple sailed off the Bahamas in May 2017.

Bennett insisted he left Hellman on deck when he went to the boat's cabin to go to sleep. He said he woke up when the craft hit something, and Hellmann was gone.

The FBI says the catamaran's portholes were opened and the hull damaged from the inside.

The couple's daughter turns 3 in July. She's being raised by his parents in Scotland.