• ALI LARTER photo | Ali Larter

Credit: Jenny Anderson/WireImage

Published: Friday January 09, 2015 14:00 PM EST



The Tonight Show was the perfect platform for the Legends actress to reveal that another baby is on the way. Larter, who already has 3½-year-old son Theodore with writer hubby Hayes MacArthur, first announced the news in early August and later confessed to PEOPLE that she has a game plan for avoiding sibling rivalry. "We're definitely working him, bribing him, whatever we have to do to make sure he doesn't sneak into that crib and dangle that baby by its feet," she joked of prepping her son for big brotherhood.