Of the eight people who died after a tour bus violently collided with other vehicles on a two lane highway in California over the weekend, three were members of Luz Garcia's family.

Her former sister-in-law, Elvira Garcia Jimenez, a 40-year-old doctor from Tijuana, Mexico, had brought along her mother and her teenage son on a day trip to a Southern California ski resort with a tight knit group of her co-workers.

None of the three family members would return.

Garcia Jimenez’s son, 13-year-old Victor Cabrera-Garcia, had wanted to see snow as a way to celebrate his birthday on Jan. 13, Garcia told The Associated Press on Tuesday.

She said Cabrera-Garcia, Jimenez, and the boy’s grandmother, 61-year-old Guadalupe Olivas, were all members of her ex-husband’s family. All three lived together in a modest San Diego home.

“We are so sad. We hurt very much,” Garcia said in Spanish in a phone interview. “It’s hard because we are suffering the pain from losing members from three generations. Each one hurts equally. It’s horrible. It has been a nightmare.”

The trio was part of a party of 10 people who were employees of the Tijuana hospital and their family members, said Samuel Gasca de los Reyes, spokesman for Mexican Institute of Health and Social Services for Baja California state workers.

Thirty-eight tourists from Tijuana, Mexico were on board when the driver lost control.

“They were a very tight group,” Gasca de los Reyes said. “They were very close outside of work.”

Two people from the group remains hospitalized, he said.

As loved ones grieved, federal and state investigators combed the mangled wreckage for clues as to what caused the accident that also left dozens injured.

Authorities targeted the brakes and other equipment in their effort to explain why the driver lost control in the San Bernardino Mountains on the way back to Tijuana.

The roadworthiness of the 1996 bus loomed as a key issue after the driver told investigators the brakes failed as he descended from the popular ski area. Federal records pointed to a history of brake-maintenance problems with the European-made bus.

“We are going to look very closely at the brakes as well as every other mechanical system on the bus,” National Transportation Safety Board spokesman Eric Weiss said.

The California Highway Patrol and NTSB were collecting evidence on the bus, road conditions and possible driver error or fatigue.

NTSB officials also went to the offices of bus operator Scapadas Magicas LLC, in National City, Calif., where they interviewed owners and employees, and gathered documents on the maintenance history of the bus, Weiss said.

The Associated Press contributed to this article.

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