Six people were wounded in the shooting. Peatry was the only one who died. Detectives say the victim's ranged in age from 13 to 26.
Investigators have no motive and believe there were at least two shooters.
The Peatry family says that the 14-year-old was simply at a party when she became an innocent victim of an apparent fight that broke out.
Witnesses say at least 15 shots were fired.
"I wish no bad for anyone but that was senseless right there," said Marquis Peatry. "She was our sweetheart. I am going to really miss her. It is going to be really hard for me. I am so used to hearing her voice every day. I wasn't expecting anything like this."
"My cousin didn't deserve this. My aunt didn't deserve this. This is a lady who would give her shirt off of her back and would open her house and her heart to everybody," said Sha Sha Freeman, Dominique Peatry's cousin. "This senseless, stupid act took my cousin, her only baby girl away from her. This needs to stop."
Detectives say shots were fired inside and outside the home.
"Physical evidence at the scene would indicate that there was more than one gun involved," said Lt. Patrick Nelson. "What we're looking for is at least a lone male who appeared to have been in the company of two or three others when he arrived."
Anyone with more information on the shooting is urged to call detectives at (323) 890-5500.
City News Service contributed to this report.