BOSTON (CBS) – The Brooklyn, New York mom of 18-month-old twin boys posted a video online last month showing the boys apparently conversing. It already gotten close to two million views.

It’s hard to watch this and not believe these two have a language all their own, but an expert tells WBZ-TV, “they were not speaking.”

Dr. Jean Berko Gleason has studied how little kids learn language for more than 50 years. Now a Professor Emerita at Boston University, she says these kids are doing something called jargon babbling.

WBZ-TV’s Jim Armstrong reports.

“There are no words in there, so it is basically a kind of very expressive babbling,” she explained.

It’s exceptionally cute, she agrees, and it’s very clear the boys are “having a good time, and communicating because they were using gestures as we do. And they were smiling with one another, making eye contact. They are clearly happy, normal communicating kids. But they were certainly not talking.”

The sounds they use, she says, are not even terribly advanced for their age. But their back-and-forth is spot-on, probably because they are twins.

“I think twins have a special relationship with one another and there are many instances of private language between twins or twins who finish one another’s sentences,” Dr. Berko Gleason added.