Zara Phillip retired from competing at the Badminton Horse Trials after making a mistake on the cross-country course.
After a good start during yesterday's dressage stage, Phillips - who was riding High Kingdom - missed the second of two brush jumps in the Lake and pulled up.
It means she can no longer take part in tomorrow's show jumping stage.
More top news
No one gave him a chance - but Donald Trump has just pulled off one of the greatest feats in modern American political history.
German police are investigating an online picture thought to be of two British men doing a Nazi salute at a former concentration camp.
Late sunshine here and there this evening - but more cloud for southern Scotland, northern England and Northern Ireland again.