Tim Walz's Son Gus, 17, Steals the Show in Emotional Appearance at DNC: 'That's My Dad'

Minnesota Gov. Tim Walz and his family made an emotional appearance at the Democratic National Convention on Wednesday, Aug. 21, while he accepted his party’s nomination to serve as Kamala Harris’ 2024 running mate.

Walz came to the biggest stage of his career to applause from thousands in the crowd — and an emotional reception from his wife Gwen, and their two children, Hope and Gus, all of whom could be seen crying as he accepted the nomination.

"That's my dad," Gus could be seen saying, as he applauded and pointed at his dad on stage.

"Hope, Gus, and Gwen you are my entire world, and I love you," Walz, 60, told his family before the crowd at the United Center in Chicago, as Gus stood on his feet in tears, giving his dad an emotional standing ovation.

Elsewhere in his remarks, Walz — a former social studies teacher who married Gwen, a former English teacher — opened up about the couple's seven-year journey with fertility treatments before they were able to have children.

"If you've never experienced the hell that is infertility, I can guarantee you you know somebody who has," Walz said, recounting the "absolute agony" of the years of treatments he and his wife underwent.

Tim and Gwen opened up to PEOPLE in August about Gus, who was diagnosed with a non-verbal learning disorder, ADHD and an anxiety disorder as a teenager.

"Like so many American families, it took us time to figure out how to make sure we did everything we could to make sure Gus would be set up for success as he was growing up," the couple told PEOPLE.

"It took time, but what became so immediately clear to us was that Gus’ condition is not a setback — it’s his secret power."

The vice presidential nominee’s broader speech laid out his vision for a Harris-Walz administration, and took aim at his Republican opponents, Donald Trump and J.D. Vance.

"Here's the thing, it's an agenda nobody asked for...and serves nobody but the richest and most extreme amongst us," Walz said of Trump and Vance's platform. "Is it weird? Absolutely."

Walz’s DNC appearance comes less than a month after Harris, 59, selected him as her 2024 running mate.

The vice president announced that Walz would be joining her on the Democratic White House ticket on Aug. 6. Elaborating on her decision in a statement, she wrote, “One of the things that stood out to me about Tim is how his convictions on fighting for middle class families run deep. It's personal.”

"We are going to build a great partnership,” the statement continued. “We start out as underdogs but I believe together, we can win this election.”

Hours later the duo made their first joint campaign appearance at Temple University in Philadelphia, and Harris explained why she selected Walz, who stepped into his governor role in 2018 and was reelected in 2022.

"Since the day that I announced my candidacy, I set out to find a partner who can help build this brighter future,” she said. “A leader who will help unite our nation and move us forward. A fighter for the middle class. A patriot who believes as I do in the extraordinary promise of America — a promise of freedom, opportunity and justice not just for some but for all.”

"So Pennsylvania," Harris continued, "I’m here today because I’ve found such a leader: Gov. Tim Walz of the great state of Minnesota!”

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An experienced politician — and “leader,” per Harris — Walz’s resume also includes teacher, national guardsman and high school football coach. At Temple, Harris expanded upon his time in public education — including an anecdote about Walz helping a student start a Gay-Straight Alliance chapter.

The vice presidential candidate turned to politics in 2006, successfully running for U.S. Congress as a Democrat in a historically Republican district over a decade before he won the 2018 Minnesota gubernatorial race.

Since his 2022 reelection, Walz has signed legislation into law protecting Minnesotans' access to abortion, legalized marijuana and addressed calls for police reform.

In some of his earliest moments on Harris' running mate shortlist, Walz successfully dubbed some far-right Republican policies as "weird,” and, notably, articulated a sharp ideological divide between Vance and rural Americans.