His family told CBS2's Christina Fan on Sunday his attacker is someone he knew and is still in the run.
Tamara Bush broke down as the 31-year-old shared the moment she learned her older brother was killed.
"It's just unfortunate that apparently a friend did this. If you guys are friends why you fighting like this?" she said.
Police found 36-year-old Dashawn Bush unconscious early Saturday morning on Christopher Street in the West Village. Friends said the Brooklyn man was attending a birthday celebration when he got into a fight with another man. The brawl left Dashawn dead and his family desperate for answers. His sister said detectives told her the victim had no visible injuries.
"What transpired? What was the argument about? How long was he unconscious? Did he fight and he stopped fighting, because maybe he had a seizure and his heart stopped? We don't know," Tamara Bush said.
All those questions are why the family is calling on the attacker to turn himself in.
"You can explain to the police what happened. We don't know because you're not saying anything. And that makes you look guilty just by you hiding," Tamara Bush said.
Dashawn Bush was one of four siblings. His sister said he was fearless, brave, and a constant source of support to her during her darkest times.
"He was the best big brother I could ask for. When I was sick and going through chemo, he was there. Any time I called him, he was always there," Tamara Bush said.
His death is now a permanent void she said will never be filled.
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