Mickey and Minnie Mouse. (Credit: CNN) Happy birthday, Mickey and Minnie Mouse! They both turn 91 years young on Monday. The two share the same “birthday” because they made their big debuts in the animated movie “Steamboat Willie” in New York on Nov. 18, 1928. You can mark the day by watching a cartoon featuring the pair, wearing a classic Mickey Mouse watch or T-shirt or visiting a Disney theme park. Some fun facts: Mickey and Minnie both have their own star on the Hollywood Walk of Fame. Walt Disney admitted privately in 1933 that Minnie and Mickey are married, but it’s never been officially stated. Their original names were Mortimer and Minerva, and Mickey has a middle name: Theodore.