There aren't too many things that can make Marie Osmond disappoint her faithful fans -- not even a trip to the ER!
Marie's rep confirms to ET that the singer was diagnosed with bronchitis after her Las Vegas show on Wednesday night.
Marie, who suffers from allergies, tweeted that she didn't recognize her illness until she "went to hit the high notes" during her performance.
Marie was eventually released from the hospital and plans on returning to the stage tonight at the Flamingo.
"Getting ready to go to the show," Marie tweeted Thursday evening. "Big doll event tonight. Nothing could make me miss this."
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