Branson, the billionaire founder of the Virgin Group, has worked for himself from day one.At the age of 11, Branson says in a LinkedIn post, he and his best friend, Nik Powell, started breeding parakeets to sell as pets to their classmates. The birds started multiplying faster than they could sell them, so they then tried their hand in a different market.As Christmas approached, they bought small fir trees and hoped to make a profit off them once they grew big–but rabbits destroyed the trees before they could grow, he writes.