Her cousin, Sarah Wessling tells TMZ. the day she died, Jessica worked a normal day seeing patients at her practice - she was a naturopathic physician - and returned home to visit with her mother and aunt.
According to a GoFundMe arranged by her cousin, Campbell passed away unexpectedly on December 29, leaving behind a 10-year-old son.
Sarah says Jessica went to the bathroom but never came out, and when her aunt went to check on her. she found her collapsed on the floor. When her aunt when to check on her, she could not be revived.
Earlier that day Jessica had told her family she felt congested and thought she was getting a cold but did not think it was COVID-19.
The family is waiting on an autopsy form the Multnomah County Medical Examiner's office in Oregon. Results from an autopsy are expected soon. She won acclaim for her portrayal of Tammy, the rebellious lesbian student who jumped into the high school election race against the overly ambitious Tracy Flick (Witherspoon) and her brother, the popular jock Paul, played by Chris Klein.
Her first professional acting role was in the 1992 TV movie In the Best Interest of the Children; she played Julie Cain.
The Oklahoma native leaves behind a 10-year-old son Oliver and her husband of 11 years, Daniel.
And she popped up in 2001 film The Safety Of Objects opposite Glenn Close and Dermot Mulroney.
More than $22,000 has been donated so far, including a $5,000 donation by Freaks and Geeks' executive producer, Judd Apatow.
"While coping with this unexpected and tragic turn of events and planning for Oliver's future, the family is also faced with unexpected cremation, memorial, and probate expenses".