At some point over the past few months, the children were sent to live with their grandmother, Patricia Hauser, the mother of Sharyn Hakken.
Sheriff's investigators say Josh Hakken entered Hauser's home at 6:30 a.m. last Wednesday. She told police that he tied her up and fled with the children in her silver 2009 Toyota Camry. That vehicle was found later that day just a couple of blocks away from the home.
Those investigators told CNN they believe Hakken joined up with his wife, who was waiting in their pickup truck, and the family drove to a parking garage. A short time later, investigators said, Hakken is believed to have taken a sailboat out of a private slip in nearby Madeira Beach.
Surveillance images showed the boat sailing into the Gulf of Mexico about three and a half hours after the boys disappeared from their grandmother's home, investigators said, adding that the photos showed adults and children on board.