(CNN) -- He was just 4 years old when his treatment sparked international outrage. About a year later, he won an award for the world's youngest sailor. And he piloted a plane before he turned 6. Up next? Crossing the Tibetan Plateau by unicycle. Welcome to the unorthodox and controversial world of Duoduo and his "Eagle Dad." The world first met little Duoduo, as he's nicknamed, in 2012. A video surfaced of his small 4-year-old frame shivering in subfreezing temperatures. "Daddy, Daddy please hold me!" Duo cried into the camera. His tiny body was shielded from the cold and snowy New York winter only by bright yellow underwear and a pair of white sneakers. His family was in New York on vacation, but there's no time off from training when you're the son of He Liesheng.
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Duoduo piloted a plane and started an investment company by age 6
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His dad also made him stand outside in freezing cold wearing just underwear and shoes
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"Like an eagle, I push my child to the limit so he can learn how to fly," his father said
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"If a child does not go through hardship, then he cannot become strong"
Looking back on that day in New York, @placeholder remembers the cold, but he also remembers what came next.