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.
More top news
Norfolk County Council has apologised following a damning report that said it let down foster children and the carers looking after them.
Tonight investigates the increasingly sophisticated methods criminals are using to target the elderly and defraud them of their savings.
The mother of a serviceman from RAF Honington who went missing over the weekend has started a social media campaign to try and find him.