Sheryl Sandberg's thoughts on joy

Sheryl Sandberg admits she got some things wrong in her book, "Lean In." She didn't understand the challenges of being a single mom and having a career until her husband died a few years ago.

"But what I got right is the world is still run by men. I don't think that's going that well," she said.

Sheryl also said will never make another joke about being old.

Every day is a chance to experience joy.