Noting the "cosmic miracle" of his birthday falling on the same day as the premiere of Marvel pal Chris Evans's Captain America: The Winter Soldier, the Iron Man star organized a gigantic screening of the film for dozens of kids and their parents.
(That's 13 A's, by the way.)
As the screening began, Downey posted an image of himself posing with the lucky children on his Facebook page.
(That's only 5 A's.)
Downey has two sons: 2-year-old Exton and 20-year-old Indio. It is unclear if either son was in attendance at the screening.
See PEOPLE's birthday message to Robert Downey Jr. below!