UsMagazine.com said the "Inception" and "3rd Rock from the Sun" star's brother was a 36-year-old fire-spinning artist and flow arts teacher at Flow Temple Arts School in Venice Beach, Calif. He went by the nickname Burning Dan.
"My super hero brother @burningdan 1974-2010," the 29-year-old actor said via Twitter Tuesday.
"BURNING dAN brightly embodied that bold beastly bliss sometimes referred to as 'the creative spirit.' He would absolutely positively insist that we not let this bad news deter us on our collective mission," Gordon-Levitt added later on his Web site.
Celebrity Families of 2014 [PHOTOS]