Carlos Vasquez had gone to IHOP to have lunch with his parents to celebrate his birthday.
While waiting for a table at a branch in Koreatown, a woman interrupted a conversation between Vasquez and his mother. Vasquez started filming.
In the video, the woman yells at Vasquez's mother for speaking Spanish, and demands that she speak English instead. Vasquez's mother begins crying and yelling at the woman in English.
The video, which many shared on social media as evidence of racism against Latinos, has garnered more than 15 million views online since it was posted Friday.
Vasquez, who turned 24 on Saturday, said he never expected so much attention.
"I was shocked, and right now, still to see that it's still growing and growing and growing. But I'm glad it spread, because that's the point," Vasquez said in an interview with the Los Angeles Times. "I wanted people to be aware of what's going on even in the city of Los Angeles."
In the video, the woman tells Vasquez's mother to go back to Spain and that Americans fought for their freedom, and mentions Nazis and Russians.
Vasquez said his parents moved to L.A. from El Salvador in 1985. They live in downtown and his mother works as a janitor in Santa Monica.
He said that after he posted the video, he received many supportive messages -- saying things like "Please hug your mom for me" -- and also many from people saying they'd gone through the same thing and wished they'd been able to record it.
However, he said he also received messages saying his mother should learn English. He pointed out that his mother does speak English, just not perfectly.
Vasquez, who lives in Highland Park and is a teacher's assistant, said that neither he nor his parents had ever experienced anything similar.
"It was just so rare to see that in L.A.," he said.
"We were very, very shocked," he said.
He saw that the altercation drew a crowd, including many IHOP employees. He said he was disappointed that none of them stepped in.
After the incident, Vasquez said his mother didn't want to stay at the restaurant, but he told her they should still eat there. "Otherwise we're going to show the lady that she has more power versus us," he said.