Hillary Clinton tells PEOPLE she and running mate Tim Kaine are "focused on learning about each other"

Hillary Clinton and Tim Kaine Break Down Their #RelationshipGoals: 'She's the Boss,' He Says

If Hillary Clinton is elected president in November, she won’t be the only one to make history. Her running mate, Tim Kaine, would also have a groundbreaking role as the first No. 2 to the first woman president.

“She’s the boss,” Kaine says in a joint interview with Clinton for this week’s issue of PEOPLE. “The vice president has a wonderful ability to influence and promote the administration, but at the end of the day, it’s the president who has that weight on the shoulders.”

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And Kaine wouldn’t have it any other way.

“I relish that,” he says. “I’m a strong man who’s excited to be supporting a strong woman in this way.”

As for their relationship goals, Clinton and Kaine appear to be taking some cues from “ best friends forever” President Barack Obama and Vice President Joe Biden, whose bond famously extends beyond the White House walls.

For more from Hillary Clinton and Tim Kaine on their historic team and facing down Donald Trump, pick up this week’s issue of PEOPLE, on newsstands Friday

“We are very much focused on learning about each other, so that we know enough to not only have an even better relationship, but to kid each other,” Clinton says. “I’ve seen it up close and know how important it is. There’s a lot of serious stuff to talk about, but kidding each other, getting some release from all of the constant stress, that’s a big part of it, too.”

“So I’m storing up what I’m learning about him,” she adds. “I tend to interrogate his three children when I get a chance, in order to get as much information as possible.”

For his part, Kaine has already taken on a protective role for Clinton. Like when her Republican rival Donald Trump goes on the attack.

Kaine tells Clinton, “I’ve heard you say this, Hillary: ‘I don’t care what he says about me. I take personally things he says about others.’ ”

“If you’re dissing somebody with a disability, saying the American military is a disaster, trashing somebody because they’re Mexican-American, for gosh sake,” Kaine continues, listing off some of Trump’s most controversial insults. “That’s what makes her mad. Now, some of the things that Trump says about her … like, ‘Does she look presidential? I don’t think so, fellas’ – it makes me furious.”

But Kaine is confident he and Clinton will have the last laugh.

“He’ll probably be saying that at the end of her second term, when he’s hawking Trump bottled water,” Kaine quips.

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