Robert McGill and his wife seemed to be living a romance story: ex-high school sweethearts who found each other decades later and renewed their love.

So friends and neighbors were shocked to learn that the veteran Los Angeles County school teacher is accused of killing his wife on his 55th birthday during a domestic dispute on a Mexican cruise. Shirley McGill had turned 55 just six days before she died.

"It doesn't make any sense. You are talking about a situation that just doesn't have any connection to the people I know as neighbors," said Michael Hougardy, who lives on the McGills' cul-de-sac in the San Fernando Valley of Los Angeles.

"Bob and Shirley never said anything negative about each other," he told The Associated Press on Friday. "I saw Bob a couple days before they left. He was excited. He was looking forward to it."

McGill, 55, was arrested for investigation of murder and jailed Thursday after the Carnival Elation returned to San Diego.

Debra Hartman, a spokeswoman for the U.S. attorney's office in San Diego, declined Friday to say whether he had been criminally charged but said she would provide information later in the day. McGill could make a first court appearance as early as Friday afternoon, she said. It wasn't immediately known if McGill had an attorney.

The first hint of trouble came on Tuesday, three days into the five-night cruise to Cabo San Lucas, when a passenger contacted the ship's security to express concerns that a woman might be dead, said Keith Slotter, a special agent in charge of the FBI's San Diego bureau.

Crew members found the body of Shirley McGill in the cabin and later detained her husband and placed him in the brig as the ship sailed home.

McGill was a divorced father of two sons when he reconnected with Shirley through the Internet, colleagues said.

Court records show McGill filed for bankruptcy in 2001 and that the couple was married two years later in Las Vegas.

In bankruptcy papers, McGill listed assets of $50,000 to $100,000 and debts of $100,000 to $500,000. The attorney who handled the case did not immediately return a call seeking comment.

McGill, whose gray hair falls below his shoulders, played guitar, liked to ride horses and hike and "was always out every morning walking the dogs," Hougardy said.

"Shirley was his childhood sweetheart," Paul White, who owned the school where McGill taught, told the Daily News of Los Angeles. "He was happily married and loved her with all his heart."

Colleagues said McGill spent 30 years teaching at-risk teens, became burned out by the job a decade ago but was revitalized when he came to work at the West Valley Leadership Academy in Canoga Park, a county-run alternative high school that White founded to help at-risk youth. The county closed it in June because of dwindling attendance.

McGill had switched teaching jobs a few years ago and was tutoring pregnant teenagers in an independent-study program.

Shirley McGill retired last week from the state Department of Motor Vehicles and McGill had planned to retire soon as well, acquaintances said.

Hougardy said Shirley McGill planned to move to Oregon, where her family and her children from a previous marriage lived. McGill was going to join her when he retired.

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