Vice President Joe Biden is known for his speeches. But there is one particular speech Biden gave that I've never forgotten. I remember seeing it on TV, half-listening, and then, all at once, realizing Biden was saying something I had never heard him say before, something I had never heard any politician say before.

On May 25, 2012, Biden spoke to families of fallen soldiers and described the appeal of suicide.

"I probably shouldn’t say this with the press here," Biden said, "but no, but it’s more important, you’re more important. For the first time in my life, I understood how someone could consciously decide to commit suicide. Not because they were deranged, not because they were nuts, because they had been to the top of the mountain, and they just knew in their heart they would never get there again."

It's a startling speech — and it's particularly startling to hear Biden give it. Biden is America's most happy-go-lucky politician. The internet delights in pictures of him eating ice cream cones, flattering grandmothers, smiling that big smile. The Onion has created an alternative-universe Biden, a guy who loves crushing beers while washing his Trans-Am shirtless.

But the real Joe Biden doesn't drink. There's too much alcoholism in his background. And the real Biden isn't as carefree as his public persona suggests. The real Biden buried his wife and one of his children before he turned 30. But somehow, he keeps smiling.

When you think of what Joe Biden's endured and what he's like, he seems to get something right about life that most of us don't. — Michael Grunwald (@MikeGrunwald) May 31, 2015

In 1972, a week after Biden was elected to the Senate at the age of 29, his wife and daughter were killed in a car crash. They had been out Christmas shopping, and they were hit by a tractor trailer. His sons were also hospitalized. It wasn't clear that they would survive. If they did survive, there might be brain damage.

In his book What It Takes, the late Richard Ben Cramer described the scene that confronted Biden at the hospital:

The doctors came out to find him: "We lost Neilia and the baby." The boys were still being worked on— broken hips, legs, arms. Beau was all cut up, and Hunter— concussion. Doctors weren’t sure ... brain damage possible. They’d have to transfer Hunt— another hospital, top pediatrics ... they had to get Beau into traction [...] They moved the boys to a private room. The boys’ legs were going into spasms. Shots, IVs, traction. Joe wouldn’t leave. He focused. The boys. This boy. His leg. Raise the bed. That lever. That cloth. Wet the cloth. ... His boys were all that was left. [...] Sometimes he thought it would be easier ... if he were the only one left ... then he could kill himself. It was the boys, kept him alive.

Biden's political career almost ended before it began. He almost resigned his seat before he took it. But he ended up taking the oath of office. He took it at the side of Beau's hospital bed.

Biden took his 1973 Senate oath at the bedside of his children who were injured in crash that killed his wife. pic.twitter.com/DDqwcucsD9 — Andrew Kaczynski (@BuzzFeedAndrew) May 31, 2015

In the decades after, Biden would commute to and from Washington on the train, trying to get home each night to see his children. In a recent speech at Yale, he said that bond with his sons was his "redemption":

I began to commute thinking I was only going to stay a little while — four hours a day, every day — from Washington to Wilmington, which I’ve done for over 37 years. I did it because I wanted to be able to kiss them goodnight and kiss them in the morning the next day. No, "Ozzie and Harriet" breakfast or great familial thing, just climb in bed with them. Because I came to realize that a child can hold an important thought, something they want to say to their mom and dad, maybe for 12 or 24 hours, and then it’s gone. And when it’s gone, it’s gone. And it all adds up. But looking back on it, the truth be told, the real reason I went home every night was that I needed my children more than they needed me.

Biden's son Beau was diagnosed with brain cancer in August 2013. In November of 2013, after treatment, the cancer seemed beaten. It returned in May 2015. And now Joe Biden will have to bury another child.

In that 2012 speech, Biden talks about the constant weight of grief. "Just when you think, ‘Maybe I’m going to make it,’ you’re riding down the road and you pass a field and you see a flower, and it reminds you. Or you hear a tune on the radio. Or you just look up in the night. You know, you think, ‘Maybe I’m not going to make it, man.' Because you feel at that moment the way you felt the day you got the news."

Biden doesn't end the speech easy. He doesn't say the grief ever goes away. He just says, eventually, it makes room for other things, too.

"There will come a day – I promise you, and your parents as well – when the thought of your son or daughter, or your husband or wife, brings a smile to your lips before it brings a tear to your eye," Biden says. "It will happen."