The shots rang out Monday afternoon on Old Farm Road in the city's Mid West neighborhood, according to police.
Despite the man's efforts to protect the child, the 11-year-old was still wounded. The boy remains in a hospital in critical condition.
The identities of both victims have not yet been released by authorities.
But, according to the victim's ex-girlfriend, the man killed was Emanuel Solomon, who was known as a rapper on YouTube called "Montana22."
The ex said Solomon lived at the complex with his girlfriend and her son, who was injured.
Police believe three armed suspects were waiting at the complex before they opened fire. The group then got into a waiting vehicle and drove away. HPD described the suspect vehicle as a black Pontiac sedan.
Eyewitness News returned to the complex on Tuesday, where neighbors expressed fear and emotion over what happened.
Despite the anxiety caused by the shooting, neighbors recalled a happier time with the boy when they built him a bicycle. Neighbors said they cheered the boy on when he started riding it.
As of Tuesday, police have not made any arrests and have not released descriptions of the suspects.
Police are reviewing home surveillance camera footage that may help them in the investigation.
According to family, the 41-year-old Solomon leaves behind three children.
The shooting was just one of the multiple incidents that police dealt with all in one evening.
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One of the incidents involved a 16-year-old girl who died during a confrontation over what police called a "social media beef."
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