An Arroyo Grande teen died Tuesday, four days after she and a friend from Grover Beach were seriously injured in a vehicle collision just west of Bakersfield.

Chelsea Holston, 18, died at 10:40 p.m. Tuesday at Kern Medical Center, where she and Amber Davenport, 17, were admitted the night of the March 30 accident.

Davenport was listed in serious condition, hospital spokeswoman Cindy Morgan said Friday. Davenport's mother, Jocelyn Mercado, said her daughter suffered a broken pelvis, a bruised lung and head trauma and, as of Friday, was semi-comatose.

Holston apparently had massive head trauma and survived an emergency surgery hours before her death, a close friend, Marni Raue, said Friday. Holston was surrounded by relatives in her hospital room Tuesday when she was taken off life support, she added.

Funeral arrangements are incomplete.

According to a California Highway Patrol officer based in Buttonwillow, Holston was driving a 2006 Ford Ranger north on Highway 43 around 8 p.m. March 30.

The Ranger appears to have slowed to 10 mph at an intersection where Highway 119 meets Highway 43, between Taft and Bakersfield, a CHP report said.

Holston, with Davenport as a passenger, failed to obey a stop sign and entered the path of a big rig truck coming west on Highway 119, the report said.

The truck driver, Armando Alarcon, 38, of Cuyama, reportedly could not stop and slammed into the Ranger's passenger side. Both vehicles ended in the northwest corner, where the Ranger's driver side struck a metal light pole.

Holston and Davenport were airlifted to Kern Medical Center. Alarcon suffered minor injuries, according to the CHP.

Raue said her friend's trip was routine.

Holston was known for traveling between Bakersfield, where she spent the early part of her adolescence, and Arroyo Grande, where her family moved in 2004, Raue said.

Holston had made plans to drive her sister to Bakersfield for a birthday party, Raue said. But in the end Holston drove without her sister. Davenport joined on the trip as a friend, said her boyfriend Kevin Garceau, who was on the phone with her when the accident occurred.

Davenport and Holston were both seniors at Nipomo High School, friends and relatives said. They swam together in the varsity swim team, Mercado said.

Earlier that day Holston had stopped to get lunch where she worked as a server at Alex's Bar-B-Q in Shell Beach for the past nine months, said restaurant owner Harry Lindell.

Holston had requested the weekend off to visit friends and family in Bakersfield, he added.

"I went by to say hello to the girls and then went on my way," said Lindell. "I didn't know there would be an accident that night."

Lindell said Holston was a "level-headed" person with an excellent work habit and worked her way up to her current position.

"She will be missed," he said.

High school officials could not confirm, but Raue said Holston was taking advanced high school courses at Cuesta College during her last semester as a senior.

"You'll never meet another person like Chelsea," Raue said. "I'm going to miss the connection we had."