Reese Witherspoon is paying respects to her “Election” co-star Jessica Campbell.

Campbell, a naturopathic doctor and former actress, died suddenly and unexpectedly on Dec. 29 at age 38. Witherspoon learned of her passing and shared her mourning online.

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“So heartbroken to hear this. Working with Jessica on ‘Election’ was such a pleasure,” Witherspoon tweeted after learning of the tragic news. “I’m sending all my love to Jessica‘s family and loved ones.”

“When I think of Jessica I remember a shy, incredibly sweet, very pink-cheeked teenager who liked to discuss with me what is best to order at Applebee’s,” said fellow co-star Matthew Broderick in a statement to The Hollywood Reporter.  “She was very dear and an extremely good actor. Heartbreaking news. My deepest sympathy to her son and the rest of her family.”

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Campbell was visiting her mother and aunt after working with patients. She reportedly felt congested, entered a bathroom and never came out. Her aunt found her unresponsive and was unable to revive her. The family is currently awaiting autopsy results.

“Election” was released in 1999 and starred Witherspoon, Campbell, Broderick and Chris Klein. Campbell also made appearances in “Freaks and Geeks” and “The Safety of Objects”.