Former NFL running back Herschel Walker would help stop the Democrats' "agenda to turn America into a third-world hellhole," Christian told the crowd.
The 23-year-old influencer, who has built an online following with a series of sassy right-wing rants, appeared to be the fully supportive son he had told his Instagram followers he was back when his father kicked off his campaign in August 2021.
"I’m so proud that he’s chosen to step up to the plate and do this for our great country," Christian had written on Instagram.
Late Monday night, that supportive image blew up in dramatic fashion.
In a series of astounding tweets, the young Walker turned on his father, calling him a deadbeat and a liar.
"Every family member of Herschel Walker asked him not to run for office, because we all knew (some of) his past. Every single one. He decided to give us the middle finger and air out all of his dirty laundry in public, while simultaneously lying about it," Christian tweeted. "I’m done."
The young Walker was reacting to a bombshell story published by the Daily Beast, which reported that the Republican candidate to represent Georgia, who has been running on a platform opposed to abortion rights, had urged a woman he impregnated in 2009 to get an abortion and had paid for the procedure.
The woman, whose identity the Daily Beast did not reveal, provided the outlet with a copy of a $700 check from Walker, a receipt from the abortion clinic, and a "get well" card he had signed for her.
Herschel Walker subsequently released a statement on Twitter in which he called the story a "flat-out lie" and said he would file a lawsuit against the Daily Beast on Friday morning. (A lawyer for Walker told CBS News on Tuesday they were still considering their options and had not made a final decision.)
"This is another repugnant hatchet job from a Democrat activist disguised as a reporter who has obsessively attacked my family and tried to tear me down since this race started," he wrote.
In June, the same outlet reported that Herschel Walker had a second son, in addition to Christian, whom he had not publicly acknowledged. That boy's mother had taken Walker to court a year after giving birth in order to force him to acknowledge his paternity and pay child support, the Daily Beast reported.
The candidate, who has been a frequent critic of absentee fathers, subsequently admitted he had a total of four children, three of whom he had not discussed in great detail. He denied that the children were "undisclosed," instead insisting he had chosen not to talk about them on the campaign trail in the same way he did about Christian.
But Monday's latest revelation from the Daily Beast was apparently enough to push Christian over the edge.
To a stunned online audience, the young Walker said his father had been violent against him and his mother, and was now pretending to be a "moral, Christian, upright man" in order to win conservative votes.
Following Christian's tweets, Herschel tweeted simply, "I LOVE my son no matter what."
Christian then retweeted that post, adding, "You have four kids that we know of and you weren't in the house raising ONE of them, you were out cheating and lying."
"If you loved your kids you'd be raising them instead of running for a Senate race to boost your ego," he wrote, before subsequently deleting that post.
The Walker campaign did not respond to requests for comment from BuzzFeed News on Monday or Tuesday.
But on Tuesday morning, Christian released two videos on Twitter, in which he further attacked his father and explained that he was doing so because he was angry at what he said was his dad's hypocrisy.
"I was silent lie after lie after lie. The abortion card drops yesterday. It's literally his handwriting in the card. They say they have receipts. Whatever. He gets on Twitter. He lies about it," Christian said. "OK, I'm done. Done! Everything has been a lie!"
Christian said he had initially supported his father's bid for office, which was also fully backed by Trump, because he and his mother had been assured that Herschel would own up to past misdeeds and take accountability.
"He didn't do any of that," Christian said. "Everything's been a lie. Everything's been downplayed. Everything's been cutting corners."
Herschel Walker is challenging Democratic Sen. Raphael Warnock in the Georgia Senate race, and recent polls suggest Walker has only a narrow lead.
One of the pro-Warnock ads has detailed the previous allegations of domestic violence made by Christian’s mother, Cindy Grossman, against Herschel, including him choking her and putting a gun to her head. Herschel had blamed his behavior on prior mental health problems.
Despite these allegations receiving widespread airplay in Georgia, conservative commentator Erick Erickson said that he felt Monday night's revelations were the most damaging.
"Walker hasn't mounted a good response to any attack, and this is brutal, probably a KO," he tweeted.
An unnamed Republican official allied with Walker told the Atlanta Journal-Constitution that Christian would be “solely to blame if Herschel loses the race.”
Florida Sen. Rick Scott, the chair of the National Republican Senatorial Committee, blamed Monday's developments, without evidence, on Democrats. He said Republicans and Georgians would stand with Walker.
“When the Democrats are losing, as they are right now, they lie and cheat and smear their opponents. That’s what’s happening right now," Scott said in a statement on Tuesday. "They know they are on the verge of losing the Senate, and they know that Herschel Walker is winning, so they have cranked up the smear machine."
Trump also released a statement on Tuesday afternoon, saying Walker was being "slandered and maligned" by the press.
"Herschel has properly denied the charges against him, and I have no doubt he is correct," Trump said. "They are trying to destroy a man who has true greatness in his future, just as he had athletic greatness in his past."
But Christian said he no longer cared about the Senate race and was only speaking out now because he was sick of what he said were his father's lies.
"You don't get to pretend you're some moral family guy. You don't get to pretend all these things," Christian told his father. "Talk policy. Talk normal. Do not lie!"