#1 New York Times Bestseller! Everything is... MAMA! Jimmy Fallon , one of the most popular entertainers in the world and NBC's Tonight Show's host, was on a mission with his first children's book to have every baby's first word be DADA. And it worked! A lot of babies' first words were DADA. However, everything after that was MAMA. So take a lighthearted look at the world from your baby's point of view as different animals try to teach their children that there are other words in addition to MAMA for familiar objects and activities.