As has Joker’s Daughter in the “New Suicide Squad” run. That character was not literally his daughter, but a psycho who worships him and wears his face as a mask after his death in a New 52 ...
No one else stood a chance. Ryan Gosling’s all about one-off roles that bring something fresh, and let’s face it, the Joker in Suicide Squad wouldn’t have been the same with Gosling in the role.