Kelly Osbourne is still in the hospital after she suffered a seizure on the set of her television show, and she says doctors are still trying to determine what caused the frightening episode.

“Thank U all 4 UR beautiful well wishes yes I did have a seizure they are just trying to figure out why,” Kelly Tweeted from her hospital bed with a picture of her tattooed arm with an IV.

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The Fashion Police host, 28, was working on Thursday when she turned to her co-stars and said “I don’t feel well,” and collapsed on the ground.

An audience member rushed to her aid, and she was quickly taken by ambulance to a Los Angeles hospital.

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Kelly’s family has had a difficult time lately with her brother Jack Osbourne’s Multiple Sclerosis and her mother Sharon Osbourne’s double mastectomy.

Get well soon Kelly!