Arlene Anna Hernandez of Chula Vista lost control of the eastbound 2005 Kia Sedona on Otay Lakes Road shortly after 6 p.m. Sunday, according to the California Highway Patrol.The vehicle tumbled down an embankment near Wueste Road, overturned, landed on its roof in the water and sank, CHP public affairs Officer Omar Morales said.Hernandez and a man in the front passenger seat were able to extricate themselves, but Giuliana Figueroa of La Mesa and Lesette Silva of Chula Vista remained inside until Border Patrol agents and several citizens pulled the girls out.10News learned Hernandez is Lesette Silva's mother."We heard the mom saying, 'My babies, my girls are still in there,'" said Jeunne Victorino, who told 10News he arrived at the accident scene moments after the crash. Victorino also said the woman was not alone, saying, "The boyfriend, he was bloody, like from the head down." Friends confirmed the man was Eric Figueroa, Guliana's father. Medics airlifted the children to Rady Children's Hospital, where they were pronounced dead.10News learned Figueroa and Hernandez had spent the day at the park and were on their way home when the crash happened on a curving stretch of road that some say is hard to navigate sober, much less while under the influence. "It's pretty dangerous, that's why you have to take it slow," said Victorino, who visits the park often. "I always see like street bikes racing here and I always see cars racing here. It's really dangerous." On Monday evening, about a dozen Hernandez family members visited the crash site, pausing to hug one another as two small white crosses were hammered into the ground. The crosses have the initials of both girls, and say "You will be missed." Hernandez was booked into Las Colinas women's jail in Santee on suspicion of gross vehicular manslaughter, cruelty to children and driving while intoxicated. She was being held on $400,000 bail pending arraignment, scheduled for Wednesday afternoon.