Rep. Sean Casten Wins Emotional Reelection After Teen Daughter Gwen's Death: 'It's Hard Not to Have Her Here'

Congressman Sean Casten/facebook Kara, Sean, Audrey and Gwen Casten

Democratic Rep. Sean Casten of Illinois tearfully celebrated a bittersweet win for reelection on Tuesday night, five months after the death of his teenage daughter Gwen Casten by sudden cardiac arrhythmia.

"This has been a really, really hard five months," Casten, 50, told supporters at a returns-watching party at a union hall in the Chicago-area suburb of Burr Ridge. Casten's wife, Kara, and younger daughter, Audrey, 14, stood nearby, holding hands.

"The last time I did an election in a room this big, Gwen was up here with us," said Casten, his voice choked by emotion.

"I have a picture on my desk of all of us in that moment and there's such joy on her face, it's hard not to have her here," continued the businessman and scientist who was elected to his first term in the U.S. House in 2018.

Wiping tears from his eyes, he looked to his left — at his wife and Audrey — and went on: "I'm so lucky to have you two."

RELATED: U.S. Rep. Sean Casten's 17-Year-Old Daughter Has Died: 'She Was So Loved'

VoteCasten/Twitter Gwen Casten

Gwen was 17, freshly graduated from high school and preparing to study environmental science at Vermont University this fall, when she went to sleep on June 12 and never woke up. Her mother found her unresponsive in her bed the next morning. The family later released the cause of death as sudden cardiac arrhythmia, explaining in an Instagram post: "in layman's terms, she was fine, and then her heart stopped. ... We don't know what caused the arrhythmia, and likely never will."

An honor student, Gwen was known as a compassionate activist at Downers Grove North High School, where she founded the Empowerment Club. Shortly before her death, she appeared in one of her father's campaign ads, talking about how she would turn 18 this year.

"Lots of milestones," Gwen said in the ad. "Like voting for the first time. But not just for anyone ... Sean Casten. My congressman. But I just call him Dad."

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On Tuesday night, that dad asked his team of staff, volunteers and supporters to carry on Gwen's legacy.

"Tonight is not a night to dunk on the other team. It's not a night to conclude that some parts of our community are good and other parts are irredeemable. It's a night to reflect on how tonight happened," Casten said.

"On a personal level, I can't stand here tonight without [Kara] and Audrey. We've spent the last five months doing our best to be each other's rocks — to give stability when we could and space when we couldn't, doing our best to remind ourselves as much as we could by reminding each other that life is fleeting and we had better make the most of the time that we have together because when the sadness and the fear and the pain finally washes away, the one thing that's left is love.

"Let's all do everything we can to shore that up," he continued. "First with each other and then by expanding that circle of love because that's where you find the hope."