Girl, 11, brain dead after hit-and-run ATV crash in Apple Valley desert that killed her childhood family friend

A heartbroken family is saying their final farewells to an 11-year-old girl, who has been declared brain dead Wednesday from the injuries she suffered in a hit-and-run ATV crash that also killed a 12-year-old boy who was a close family friend.

"My daughter Tina, Christina Bird was taken way too young by a senseless act by a human being," said her mother Felicia Nunez. "At 8:50 p.m., this morning the doctors came in to perform the final tests to determine that she is brain dead."

According to social media posts from family, Christina Bird of Huntington Beach died just before 9 a.m. Wednesday after the Saturday night crash that killed a family friend she has known for years, 12-year-old Jacob Martinez of Moreno Valley. However, CBSLA's Michele Gile reports the girl has been declared brain dead and remains on life support Wednesday at Loma Linda Children's Hospital. The family plans to take her off life support in the next 48 hours.

"They have a little piece of her still left," said uncle Ernie Nunez. "we can just hear her heartbeat whenever we want to go back to that — to know that she's still around."

In an Instagram post, the children were described as children who always shared family events together, even though they were not siblings.

"This tragedy of their life being taken hurts so much that they share this day together," user cynnmonique wrote. "My brother who was only 12 years old and sister whose 11 years old DID NOT deserve to be treated as their life did not matter."

In an extensive post describing the suspect vehicle, witnesses said the driver that hit the children did not stop after the crash, but was aware of it because they turned off their lights and left the scene quickly. Another witness told authorities they saw "strange" off-roaders in a damaged yellow Can-Am UTV come to their campsite and overheard them say they "need to get out of here."

The post also described the severe injuries the children sustained in the crash. Jacob's helmet was ejected in the crash, and he died at the scene. Christina was described as having suffered two broken arms, two broken legs, and injuries to her pelvis, spinal cord.

"Our family is devastated. The kids and our families loved the desert," the post said. "It was our annual trip and one time to spend time together and enjoy our families who all live in different cities," the post said.

The suspect ATV was described as an orange Polaris RZR missing its front hood with damage to the bottom of the vehicle.

"You should have just stayed and I wouldn't have been so angry but I'm so angry with you," said Nunez, directed to the suspect. "How could you do this and not help them? But you are a coward and you left and fled... you left these two babies there to die alone."