Kelly Osbourne has tweeted to say doctors are "trying to figure out" why the star had her seizure.
Tweeting an image of her arm, from what looks like a hospital bed, she said:
"Thank U all 4 UR beautiful well wishes yes I did have a seizure they are just trying to figure out why?"
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The position, posted on the British Monarchy website, pays £16,000 a year for 20 hours a week.
The parents of missing 15-year-old Bristol schoolgirl who is believed to be heading to Syria have urged her to come home.
I think it is fair to say that was the best speech I have seen David Cameron give in the decade I have been reporting on him.