"It was later when we sort of went through what happened we thought how lucky we were, 'cause if she hadn't told us, we would have just kept on walking," he said. "I'm convinced we would have died, absolutely convinced."
Tilly's fast thinking saved her entire family and many tourists that day. All it took was knowledge and then acting on that knowledge to turn a potentially deadly day into a heroic one.
Ripley said Tilly was a perfect example of what people are capable of in a disaster situation.
"This is a story that gives us a lot of hope," she said, "because if a 10-year-old girl can save people from a tsunami with basic information, then certainly we are all capable of that."
As for Tilly, she said she "was just so glad that we were all safe and together."
To find out what kind of a survivor you are, take the Survivor IQ test.