Stanesha Nicole Allen, 31, of Lake Los Angeles caused the crash about 6:15 a.m. "due to her intoxication," CHP Sgt. Denise Joslin said.
The CHP said the 2002 Toyota Sequoia drifted off Avenue I onto a dirt shoulder near 60th Street East and flipped multiple times.
A 2-year-old boy, Allen's foster son, suffered major injuries, including an amputated foot and head trauma. Her 4-year-old daughter suffered major head trauma as well.
The two critically injured children were airlifted to Antelope Valley Hospital. Paramedics took the remaining four children to Antelope Valley Hospital with injuries described as moderate to minor.
Officers said Allen's two other biological children, another foster in her care and her 10-month-old niece suffered moderate injuries.
"It's one of the most difficult calls that we handle, seeing children hurt," said Officer Joshua Wupperfeld at a Sunday afternoon press conference. "Always in all of our calls they're high priority. When we see kids that are hurt, it hits home."
Paramedics also rushed Allen to Antelope Valley Hospital, where she was hospitalized with moderate injuries and arrested for suspicion of drunken driving and child endangerment.
The CHP said they believe the woman was drunk based on breathalyzer and field sobriety tests. Wupperfeld said Allen had been at a wedding that night.
"She going to remain in the hospital for a couple of days," Joslin said, and more criminal charges are pending.
"I think she was a very nice person. the things I saw, she was a good mom and a good foster mom, I think," said Allen's neighbor, Bernice Espinosa.
The crash scene was on a two-lane, paved road in agricultural fields, about 5 miles east of Lancaster and 20 miles northwest of Lake Los Angeles.
City News Service contributed to this report.