A 7-month-old baby boy who authorities say was pushed from the fourth story of a Southern California hospital parking structure by his mother died of his injuries on Wednesday.

Noe Medina Jr. died on the same day that his mother, Sonia Hermosillo, made an initial court appearance on charges of murder and assault on a child likely to cause great bodily injury or death.

An Orange County Superior Court judge postponed the arraignment for Hermosillo, 31. She was being held on $1 million bond and also subject to a no-bail U.S. Customs and Immigration Enforcement hold.

Hermosillo, who is married and has two other children, faces a maximum sentence of 25 years to life in prison if she is convicted at trial.

Prosecutors say Hermosillo is accused of driving to the Children's Hospital of Orange County parking garage on Monday evening, removing the helmet her son wore for medical reasons and pushing him off.

Hermosillo then went into the hospital to validate her parking before fleeing the scene, an Orange County District Attorney's spokeswoman said.

The boy was treated regularly at the hospital for his health issues, the spokeswoman said, but did not have an appointment on that day.

A witness who saw him falling through the air called 911. Hermosillo was taken into custody after police spotted her car, which had been captured on a surveillance camera at the parking structure.

Orange police spokesman Dan Adams said Hermosillo, who lives in nearby La Habra, had been interviewed by detectives and that there was sufficient evidence to determine that the fall was intentional.

We're certain that she did it on purpose, let's put it that way, Adams said.