Rossy Borquez and her son, Atiel, died last week in a fire that investigators believe was intentionally set. Police believe her ex-boyfriend doused the home, Borquez and himself in gasoline.
Both collapsed in flames outside the home, while her son was found burned to death inside.
New details in Montebello fire that killed 3, including 13-year-old; domestic violence suspected
On Wednesday, the community gathered by a growing memorial of candles, balloons and flowers outside the burned home and sang "Happy Birthday" to the boy who didn't survive to celebrate.
"The thing that has me struggling is how a kid so young lost his life, and the only reason he came here was to get a better education and build a life," said Aaron Higareda, friend of the teenage victim.
Neighbors say the mother and son had re-located from Mexico - a better life in the U.S. was cut short with a tortured death.
Community members say healing will only come with collective faith.
Neighbors say another family of five people is now essentially homeless because they lived above the mother and son in the same building.