SNOQUALMIE, Wash. -- Troopers say a 14-year-old girl was driving drunk with her mother passed out in the passenger seat when she lost control and flipped the van Tuesday morning on Highway 18.

The girl was thrown from the Dodge Caravan and suffered severe head and spine injuries, but is expected to survive. Her 32-year-old mother Tuana Eyle was not seriously injured.

The crash, which occurred about 5:30 a.m. in the eastbound lanes near Tiger Mountain, brought traffic to a standstill, and part of the highway was closed for several hours while troopers investigated the crash.

Trooper Cliff Pratt said malt liquor containers were found inside the vehicle and both the teen and her mother appeared to be heavily intoxicated.

"She was so intoxicated talking to troopers at the scene she couldn't even remember her date of birth," Pratt said of the young driver.

Pratt said the mother told troopers varying stories, claiming at different times to be the girl's sister or cousin. The two had just left a private house party near the Muckleshoot Casino, troopers said.

Both are being treated at Overlake Hospital.

A family friend said Eyle and her daughter live with Eyle's mother in Auburn. Morning Star said no one knew the two had left.

"They were really worried," she said.

Star said Eyle's family saw the wrecked van on the news and had to call the hospital to find out Eyle and her daughter had crashed.

"Stressed, worried, scared, frantic," she said.

Star claims Eyle is a good mother who just made a poor decision.

"She's just a good person. People are not perfect. I'm not perfect," she said. "People make mistakes."

Pratt said both the driver and her mother could face a long list of charges, including vehicular assault, DUI and reckless endangerment.