Garden Grove Police said Erick Molina and his dad, Jorge Molina, lost their lives Saturday night while crossing.
"He just loved life. He was such a good loving boy," said Lorena Molina, Jorge's sister. Lorena said she was crushed when she heard what had happened.
"The lady at the donut shop said that he had just bought some donut holes for Erick and that he had decided that he was going to go to 7-Eleven to buy him a Slurpee," Lorena said.
Officers said Jorge Molina was crossing the street illegally with his son when a truck hit them.
"It was one of those trucks that are really tall with huge tires. They say...they didn't know if he didn't see him, but he ran over Erick first and then he ran over my brother," Lorena said.
Investigators said the driver stayed until first responders arrived. The father and son died at the scene.
Erick and his dad were a common sight around their neighborhood - a single father and his boy in a stroller. Erick couldn't walk.
"He had special needs. He always carried him in the stroller. Unfortunately, my brother lost his car about six months ago. He had a van, but he had to sell it and he was not able to purchase a new one so they would always walk around," Lorena said.
The Molina family was planning two funerals, waiting for a police report and answers about the fate of the truck driver.
Memorials honoring Erick and his father were on Garden Grove Boulevard near Benton Street.
Police said it didn't seem like the driver of the truck was distracted, speeding or intoxicated, but the investigation was ongoing.