Just over a week ago, Collao was at a party hosted by two gay teens, when another group of teens who were uninvited arrived and refused to pay the entry fee.
They reportedly started causing trouble, yelling anti-gay slurs. Collao decided to leave.
The trouble-making group allegedly followed him and chased him a block away on 90th Street. They are accused of beating him with a pipe; he later died.
Police have arrested five suspects thus far in connection with the deadly attack on Collao, who passed away after he was taken off life support. At least one of the suspects is a juvenile. All were charged with manslaughter and assault as hate crimes.
At Thursday night's vigil, Collao's 14-year-old sister, Karen Collao, stood holding a big poster board photo of her smiling brother.
"He was this person and you meet him and you're like, 'Oh my god where have you been my whole entire life?' He was that type of person," she said.
The four men accused were arrested and charged with manslaughter as a hate crime.
City Council Speaker Christine Quinn was at the vigil, denouncing anti-gay violence.
"That is what happens when hate goes unchecked. That is what happens when you allow homophobia and anti-immigrant sentiments to fester in a society," said Quinn.
Anthony Collao was not gay, but Thursday night he had the full support of the gay community. And a sister who still can't believe her brother is gone.
"It just broke my heart completely because losing your older brother, blood running through, it just hurt. It's a pain you can't imagine," she said.
"If he was gay or if he wasn't why does it matter to you?" she said. "Let him be."