A supermarket worker from Surrey is being hailed a lifesaver after tracking down a missing four-year-old girl thousands of miles away.
Harry Brown found Yvette Henley after making contact via Facebook with her estranged father, who had taken her to a US motel.
Mr Brown had an online chat with Virgil Henley and teased out his address by offering to order pizza for him.
Yvette's grandfather and guardian Gary Forester said: "Harry saved her life."
Mr Brown, 21, from Stanwell, was alerted when Mr Forester sent him a message after spotting that he was "friends" on Facebook with Mr Henley.
The 28-year-old had disappeared from California with Yvette and his girlfriend.
A court had granted Mr Forester and his wife, Kim, custody in June.
Police in the US could not find her after almost two weeks of searching, but Mr Brown, who had had occasional contact with Mr Henley via Facebook, managed to find out where the family were staying within two days.
Mr Brown, who works at Sainsbury's, had previously become "friends" with Mr Henley on Facebook through a third party but he did not know him personally.
He told the BBC: "The conversation just continued until he gave me his motel address and room number."
He said the idea of offering to buy Mr Henley pizza just popped into his head. "I eat so much pizza in my life [the idea] just came to me."
Mr Brown forwarded the details to Mr Forester, who alerted police in Arizona. And instead of pizza, Mr Henley found police at his door.
Mr Forester said: "I was desperate to find her. I can't explain how much Harry helped. We had prepared ourselves for the worst.
"In my heart, Harry saved her life. I will be forever in gratitude to him for that."
San Bernadino County Sheriff's Department confirmed Mr Forester had reported Yvette missing on the day he was granted guardianship and that child protection services had collected Yvette from an address in Arizona.