We're told she was taken to a hospital in Sherman Oaks.
A source connected with Mueller tells TMZ she had a temperature of 105 and could have pneumonia.
Brooke is supposed to be in Aspen court Friday for a hearing in the Charlie Sheen domestic violence case.
It's almost certain the hearing on Friday in Aspen will not take place.
Ironically, Charlie is prohibited from visiting Brooke or even calling her in the hospital.
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