"The two that were shot were neighbors. They were celebrating a backyard barbeque," according to Lt. Pat Nelson of the Los Angeles County Sheriff's Department.
Witnesses say two men fired several shots into the crowd, and fled in a white SUV.
The victims were identified as 36-year-old Jose Villa and 43-year-old Candido Salazar.
The wounded 2-year-old is expected to survive.
"She was holding the baby in her arms and in the back of the baby, you could see the bullet hole which was very sad," said neighbor Carlos Pacheco. "She kept on telling the baby, 'Hold on, hold on, you know. Hold on, baby, hold on baby."
Anyone with information is asked to call the L.A. County Sheriff's department at (323) 890-5500.