Axios' Mike Allen sat down with former Vice President Joe Biden for Sunday's Axios on HBO, and he noted that when asked about potential running mates recently, Biden mentioned several women but didn't name Sen. Elizabeth Warren (D-Mass.). Biden said sure, he would add Warren to the list, but even talking about vice presidential picks is "presumptuous" at this point. "The question is, would she add me to her list?" he added.

Allen also addressed the elephant in the room, asking Biden what he believed his son Hunter was doing "for an extraordinary amount of money" on the board of Ukrainian gas company Burisma while he was vice president. "I don't know what he was doing," Biden said. "I know he was on the board, I found out he was on the board after he was on the board. And that was it." "Isn't this something you want to get to the bottom of?" Allen asked. "No, because I trust my son," Biden said. "There's nothing on its face that was wrong. Look, if you want to talk about problems, you know, let's talk about Trump's family. I mean, come on."

What "guardrails," Allen asked, would President Biden "have to be sure that your son, your brother Jimmy, doesn't do anything to trade on the family name?" "They will not be engaged in any foreign business because of what's happened in this administration," Biden said. "No one's going to be seeking patents for things from China. No one's going to be engaged in that kind of thing."

Biden refused to speculate on whether older voters are wary of Mayor Pete Buttigieg's sexual orientation, but he did say he's happy Mayor Pete has a husband.