Two of the most significant Republican donors in the U.S. are getting an image makeover. The Koch brothers -- Charles and David -- gave their first-ever joint interview Tuesday as part of a publicity tour they hope will remove some of the mystery surrounding their famously large donations to Republican politicians.

In the interview on MSNBC’s “Morning Joe,” the billionaire brothers talked about everything from their childhood together and why they enjoy donating money to a previous run for office and foreign policy in the 2016 election.

The Kochs rose to prominence after funding the conservative tea party movement in recent years, and have gained more attention as they spent millions of dollars trying to defeat President Barack Obama. They plan to spend $250 million to elect Republicans to Congress and the White House in 2016, according to The Hill.

The brothers are known for avoiding media attention and typically do not enjoy giving interviews. However, they recently decided this needed to change so they could define their own image rather than letting political opponents control their media narrative, the Hill reported. Charles Koch, the older brother, has given a number of interviews over the past few months, and published a book called “Good Profit,” in which he details his management philosophy.

In addition to the publicity push for the brothers themselves, the Kochs are hoping their company can become friendlier, too. A new branding strategy by Koch Industries Inc., dubbed “We Are Koch,” aims to give character to the corporate conglomerate by telling the stories of its 60,000 employees.

The MSNBC interview took place in the brothers’ childhood home, where they joked about David Koch -- the younger brother -- cleaning up his elder sibling’s bad behavior.

“I was very good,” David Koch said, laughing. “I helped Charles correct some of his terrible behavior.”

Charles Koch added: “Everything he did wrong, I taught him the tricks on how to do it.”

Beyond traditional interviews, the Kochs have also taken to social media platforms to promote their brand and gain attention recently. Last month ahead of Halloween, Koch Industries tweeted a photo of the 80-year-old Charles wearing a Darth Vader costume.

When the Hill asked about their revamped public relations efforts, James Davis, a spokesman for their political network Freedom Partners, said the free market reforms promoted by the billionaires “benefit all Americans, particularly those most disadvantaged, and that’s an important story to tell.”

Many Democrats have criticized the brothers for their large donations and shadowy presence in the past. Democratic presidential candidate Hillary Clinton, her rival Vermont Sen. Bernie Sanders and Obama all frequently speak out against what they see as the brothers’ outsized influence on Republican politics.

But the Kochs are determined to continue spreading their wealth and supporting issues they care about, which include cutting government spending, reducing taxes, shortening sentences for nonviolent drug offenders and deregulating large businesses, such as their own.

“People aren’t going to scare me off,” Charles Koch told the MSNBC interviewers. “I’m kind of like Martin Luther when he was on trial. And he said, ‘Here I stand, I can do no other.’”