The blaze broke out on the 1400 block of East Fairfield Street at 11:15 p.m., and rescue crews were on scene within seven minutes.
"I don't know what happened. My mom started screaming, and me and my brothers just jumped out the back window," said fire victim Leo Bayn.
As firefighters worked to put out blaze from above, the front lawn of the home became a triage, with paramedics treating everyone who escaped. An extended family of 12 was inside the home when the fire broke out.
Firefighters said the fire was extremely intense on the second floor. According to neighbors, many family members escaped through the front bedroom window on the upper floor.
Neighbor Luis Flores said he grabbed a ladder and ran over to help when he saw the blaze.
On Tuesday, the fire may be out, but the entire family is without a home.
"Everybody feels sad about it. In fact, I offered my house, I told them if they don't have a place to go, my house is open," Flores said.
The boy who suffered the burns had to be airlifted to the hospital. Ten others were taken to the hospital for smoke inhalation.
The cause of the fire has not been determined, but officials say it could be electrical and likely started on the second floor.