What the Bidens Learned from 43 Years of Marriage — and Why He Still Gives Her a Corsage: ‘I’m Just Lucky’

For all that was different about this year's pandemic-era presidential inauguration, one tiny, delicate and old-fashioned detail almost went unnoticed: the wrist corsage of gardenias on First Lady Jill Biden's arm that night.

"He surprised me with it. It's a tradition," Dr. Biden, a community college English professor, tells PEOPLE in a sit-down with President Joe Biden for this week's cover story.

"I don't know when it started — a long, long time ago. I think it was for Valentine's Day," she says. "I love gardenias and so Joe would buy me a wrist corsage of gardenias. I wore it to school to teach!"

And on Jan. 20, she wore one for the small family dance party in the White House Blue Room that replaced the traditional inaugural balls (and their virus-super-spreading risk).

"Every single special occasion," the president explains about the corsages and his wife of 43 years. "It's important to, and Jill does the same thing, let each other know that, no matter how much time goes by … she goes down the steps and—"

Here he puts his hand over his heart, tapping: "It still goes a little boom, boom, boom, boom. For real."

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But what President Biden, 78, calls "a great love affair" — his marriage to Jill in 1977, five years after he lost his first wife, Neilia, and their baby daughter, Naomi, in a car wreck, and he was a grieving single dad to two young sons — has not been all flower petals and fluttering heartstrings. 

"Jill came along at a really important point and put my family back together," he says now. "She's the glue that held it together."

They grew that family — giving sons Beau and Hunter a sister, Ashley, in 1981 — and weathered the stresses of Joe Biden's 36 years in the Senate and two failed presidential campaigns. Tragedy struck again in 2015, when Beau died of brain cancer at age 46. 

In the couple's PEOPLE interview on Jan. 27, the president explained how he and Dr. Biden, 69, have beaten the odds when so many marriages crumble — whether from the stress of loss or life in the public spotlight. 

"I've read all that data about families under pressure," he says. "I know everybody says marriage is a 50/50. Well, that's not true. Sometimes you have to be 70/30. Sometimes when somebody's down, the other one steps in. And the good news for us has been — thank God — that when I'm really down, she steps in. And when she's really down, I'm able to step in. And we've been really supportive of one another."

• Watch the full episode of People Cover Story: President Biden and Dr. Biden streaming now on PeopleTV.com, or download the PeopleTV app on your favorite device.

Adds the first lady: "With all that we've been through together as a couple — you know, the highs, the lows and certainly tragedy and loss — there's that quote that says, 'Sometimes you become stronger in the fractured places.' Over time, that's what we try to achieve."

Stronger, but not perfect.

"It's not that we don't fight and argue sometimes," says the president. "I don't know, I just think I'm just lucky."

"Well," Dr. Biden chimes in with a laugh, "after 43 years of marriage, there's really not that much more to fight about."