In an interview with PopEater, the How I Met Your Mother star revealed that he and partner David Burtka, who welcomed the children in October 2010, worked closely with a "sleep specialist" during the infants' early months.
"We had probably the most fantastic baby nurse/sleep specialist who helped us out for almost the first five months and she was phenomenal and the benefits have been incredible," Harris explained. "They're great sleepers. They sleep about 11 hours a night."
The actor, who will host the 65th annual Tony awards this weekend, went on to say that he is excited to have the twins in New York for the event.
"We're kind of grateful and thrilled to be in New York while this is happening because New York is a great city for little babies, I think," Harris said. "Just going up and down the street, there's so much to see and the parks are unbelievable."
Harris recently revealed that he plans to make jokes about troubled Broadway production Spider-Man: Turn Off the Dark during the Tonys broadcast.