One of Saroo Brierley's earliest memories about his family is how he lost them.
Like most four year olds, Brierley didn't know the name of his hometown in Northern India and had yet to learn to read and write. Born into a poor family in the 1980s, little Saroo would follow his older brothers as they would travel by train to nearby towns in search of food.
On one such journey, Brierley became separated from his brother and decided to jump onto a nearby train. From there the toddler found himself in what was then known as Calcutta -- one of the biggest and busiest cities in the world -- and was eventually taken in at a local orphanage before being adopted by an Australian couple.
Brierley first made headlines a few years ago, when he revealed how he used Google Earth and Facebook to piece together his childhood memories and locate his hometown and birth mother, 25 years after being separated from his family.
Google Earth produced this video about his remarkable journey.
With his new book "A Long Way Home," out this week, Brierley is now telling his story in his own words. In a recent interview with NPR, he described the moment he realized he had found his former home through Google.
"I traced a road back that I would follow back as a child, and before I knew it I was looking at the suburb where I had grown up, and just on the right of it was the house I had grown up in," said Brierley. "I couldn't sleep for that whole night."
During a visit to that house in the Indian state of Madhya Pradesh, Brierley was dismayed to find the house boarded up and empty. A neighbor was able to take him to his mother, who still lived nearby.
"I walked forward, and my emotions and tears and the chemical in my brain, you know, it was like a nuclear fusion," Brierley told NPR. "I just didn't know, really, what to say, because I never thought this point in time or ever seeing my mother would ever come true. And here I am, standing in front of her."
The rights to Brierley's story of how he tracked down and reunited with his family were reportedly recently bought by the Weinstein Company for a possible movie adaptation.