updated 02/01/2012 AT 8:00 AM ET
•originally published 02/01/2012 AT 12:45 PM ET
“I love watching them learn to understand language. And watching them interact with each other is fantastic,” the actor, 38, and father to 15-month-old fraternal twins Gideon and Harper, tells Parade.
Having each other also gives the twins a natural companion, and someone to explore the world with, Harris adds.