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SAN FRANCISCO (KTVU) - We are learning new details about the two Bay Area families involved in a horrific accident on Interstate 5 that claimed the lives of six people.
The crash took place early Tuesday morning near Gorman on the stretch of I-5 known as the Grapevine.
Two mothers and their four children died. Only the fathers survived.
KTVU spoke to a relative of one of the fathers who survived.
Thirty-four-year-old Aaron Ng works at SFO. His mother tells KTVU her son remains in the hospital in Southern California recovering from his injuries.
From her home in Chinatown, Ng tells KTVU how painful it is to lose her daughter-in -law Flora, along with her grandson and granddaughter.
In Cantonese she says she's heartbroken all three of them were alive and now gone. She says she last saw them over the weekend at a birthday party for her grandson who was turning 4-years-old.
She says the children's mother Flora had a job working with kids and had been married to her son for six years.
Early Tuesday, a big rig rear-ended the minivan carrying the Ng family and their friends, the Li's from Daly City. The accident happened along I-5 at the Grapevine. Mrs. Li and her two children were also killed. Ng tells KTVU the two families took trips together each year.
Aaron Ng is now recovering in a hospital in Valencia. The other father also survived.
Mrs. Ng said her son is suffering from burns on both arms.
At SFO friends of Aaron Ng are mourning the loss of his wife and children. They say they have been offered grief counseling. They described Aaron as a nice guy who is funny, smart and hardworking. They say he was taking his family to San Diego to celebrate his son's 4th birthday at Legoland.
Mrs. Ng says she doesn't know when her son will be coming home.
Friends say Aaron was scheduled to come back to work at SFO after the July 4th holiday.
A GoFundMe account has been set up following this tragedy.