The Walt Disney World resort will celebrate Mickey Mouse's Birthday on November 18, 2017:

Quote Originally Posted by Disney Parks & Resorts

...Walt Disney World Resort will celebrate with special “Happy Birthday, Mickey!” buttons, merchandise and Sorcerer Mickey Cake. To commemorate the occasion, guests can sing and dance along with “Happy Birthday” during Move It! Shake It! Dance & Play It!, Cosmic Dance Party in Tomorrowland and performances by the Dapper Dans. Plus, birthday photo props will be available at all four theme parks, and everyone who collects their photos at the parks will receive a folder with a commemorative sticker.