President Biden privately has expressed worry that Republicans' daily attacks and the criminal prosecution of his son Hunter are taking a toll on his family — and could even lead Hunter to relapse, given the family's history of struggling with addiction.

Why it matters: Hunter Biden knows this. He told Axios in a rare interview that he sees his continued sobriety as crucial not only to his life — but also to ensuring Donald Trump doesn't return to the Oval Office.

• "Most importantly, you have to believe that you're worth the work, or you'll never be able to get sober. But I often do think of the profound consequences of failure here," Hunter said.

"Maybe it's the ultimate test for a recovering addict — I don't know," Hunter Biden said. "I have always been in awe of people who have stayed clean and sober through tragedies and obstacles few people ever face. They are my heroes, my inspiration."

• He added that in this case, "I have something much bigger than even myself at stake. We are in the middle of a fight for the future of democracy."

Zoom in: A slip by Hunter would weigh heavily on the president as he seeks re-election. Republicans and conservative tabloids have relished documenting Hunter's alcohol and drug addictions.

• Hunter's actions during his struggles with addiction from 2013 to 2018, along with his foreign business dealings, will be at the center of his testimony behind closed doors Wednesday as he is questioned by the GOP-led House Oversight and Judiciary committees.
• Republicans seeking to impeach Joe Biden have been trying to find hard evidence that he changed U.S. foreign policy to help his family financially, but have yet to find it.

Last July, Hunter swore in federal court that he had been sober from alcohol and drugs since June 1, 2019.

• Starting in August 2023, he repeatedly tested negative for drugs and alcohol, U.S. Magistrate Judge Christopher Burke said at a September hearing.
• A representative from Hunter's legal team told Axios he has continued to be tested since that hearing, and has tested negative.

Hunter told Axios that his first responsibility for himself and his family is to "make it through that fight clean and sober, and I feel a responsibility to everyone struggling through their own recovery to succeed."

• He is resolute that he won't — can't — relapse. But he acknowledges that the temptation is always there for him and anyone else who has gotten sober.
• "I don't care whether you're 10 years sober, two years sober, two months sober or 200 years sober — your brain at some level is always telling you there's still one answer," he said.

Zoom out: Hunter emphasizes that his struggle isn't more difficult than anyone else's. But it's undeniable that his recent path to sobriety has been unique.

• When Joe Biden announced his candidacy for president on April 25, 2019, Hunter was still in a tailspin of addictions to alcohol and crack cocaine after a family intervention in Wilmington, Del., several weeks earlier had been unsuccessful, Hunter recounted in his memoir, "Beautiful Things."
• Hunter quietly fled to California afterward, and "quit responding to the constant calls from Dad and my girls, picking up just often enough to let them know I was alive and seeking help — which in turn gave me cover to burrow back into oblivion," he wrote.
• Still, Joe Biden entered the presidential race. Hunter later wrote that "the confidence my father has in me is evidenced by the fact that he still ran."

In the first weeks after Joe Biden entered the race, Hunter met and soon after married Melissa Cohen, a documentary filmmaker. She helped pull him out of his spiral.

• Hunter's initial sobriety date was the day they married — May 17, 2019, the day before Joe Biden's official campaign kickoff in Philadelphia.
• Hunter acknowledged in court last July that he had a "drink or two" soon after, and said June 1 of that year was his official sobriety date.

What they're saying: Hunter told Axios he hopes he can provide advice for others trying to stay sober.

• "Embrace the state in which you came into recovery — which is that feeling of hopelessness which forces you into a choice," he said.
• "And then understand that what is required is that you basically have to change everything."