Biography:From Wikipedia, the free encyclopedia. Forrest Landis (born August 9, 1994) is an American child actor. He is perhaps best known for his roles of Mark Baker in Cheaper by the Dozen and Rhett Loud in Flightplan. He has one sister named Lauren Landis. Description above from the Wikipedia article Forrest Landis , licensed under CC-BY-SA,full list of contributors on Wikipedia.