Ashlee Simpson-Wentz and Pete Wentz have sought the assistance of famed "Dog Whisperer" Cesar Millan in training their aggressive English bulldog, Hemingway.
The couple became concerned with the three-year-old pooch's tough disposition during Ashlee's recent pregnancy; that's when they recruited Cesar.
Was the obedience expert able to change Hemingway from menacing pup to sweet and gentle lamb?
Find out when the Wentzes appear on Dog Whisperer
Sunday, Dec. 28 on the National Geographic Channel.
The special episode kicks off National Geographic Channel's Dog Whisperer
Week, which runs through Friday, January 2.