When it comes to building your child's vocabulary, the answer may be in quantity, not quality.

NPR reports that University of Kansas graduate student Betty Hart and her professor, Todd Risley, wanted to figure out the cause of the education gap between the rich and poor. So, they targeted early education and headed a study that recorded the first three years of 40 infants' lives.

The conclusion? Rich families talk to their kids more than poor families.

"Children in professional families are talked to three times as much as the average child in a welfare family."

Because of this, privileged infants were getting more innate experience with the English language, while the disadvantaged were simply not hearing enough of it. This disparity widens once children attend school, where the experienced leap ahead and while the inexperienced fall behind.

Alan Mendelsohn, a pediatrician at Bellevue Hospital in New York, took their study to heart. He designed a program that coached poor families on how to talk to their infant children, encouraging more interaction.

In this month's edition of the Archives of Pediatrics and Adolescent Medicine, Mendelsohn published a study claiming his program to have measurable success.

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