As per reports, he was able to tread water for nearly 20 minutes before they were both pulled to safety, with a rescue team quickly locating them.
According to a newly-released police report cited by the Daily Mail, the child’s mom asked her daughter to pose for a photograph in front of a porthole just seconds before she lost her balance, falling backwards through the hole.

The Mail say the family had been strolling along the deck when the mom pointed to the window and “offered for her daughter to take a picture in the porthole.”
Investigators told that the mom “assumed the porthole had a window or plexiglass, and she thought that [her daughter] would be caught by the glass, but instead, she kept falling.”