I grew up in the former Soviet Union.

My parents and I lived in a communal apartment

with nine other families.

When my parents wanted to be romantic,

they would send me to look out the window.

One day my dad said,

so what do you see in the window?

I said, our neighbor's being romantic.

He said, how can you tell?

I said, because their son is looking at me.

My parents laughed.

At that moment, I felt that I was in the presence

of love as a child that made the discovery

that laughter must be the way people communicate

to one another that they're happy.

Did you know that there have been actual research

into relationship between laughter and happy marriages?

For over four decades, Dr. John Gottman,

Professor of Psychology at the University of Washington,

has studied thousands of couples

in both successful relationship

and not so successful once.

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