Frankel's foal goes up for auction in just over an hour.
Together with his mother, Crystal Gaze, who is expecting a second foal by the undefeated Newmarket racehorse, he could fetch more than £1m at the auction at Kensington Palace.
Henry Beeby, chief executive at auctioneers Goffs, said: "Frankel was the greatest racehorse we had ever seen. He was undefeated. He was spectacular. And he was an absolute star.
"It's a bit like Usain Bolt turning up at stud."
Click below to hear more from Henry Beeby.
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