You're listening to Shortwave from NPR.

Hey Shortwaveers, Sydney Lepkin and the host chair for a hot sec today.

So a few years ago, I found myself on a train.

It was the first time I'd really traveled as an adult and I was in Europe.

I was seated across the table from a French woman traveling with her toddler.

So his mom and I hid it off and spoke in English for a few hours.

Meanwhile, this little boy had a lot to say.

I couldn't understand it, but he clearly had opinions about his books, his snacks,

maybe how cool it was that his hands were attached to his arms.

And he wanted everybody to know about it.

All in what I just assumed was French.

So finally, I said to her completely earnestly,

hey, so what's he saying?

And she paused for a while and she's like, nothing.

He's a baby.

So as a reporter and now the mom of my own chatty baby,

I've taken a huge interest in baby babble lately.

So I got Shortwave to let me make a whole episode about it.

Babies even when they're very young are very good at imitating the rhythm and the

intonation of the language they're hearing.

I called up Dr. Megasunara, a professor of linguistics at UCLA.

She studies how babies listen before they start talking

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