CHICAGO (CBS) — A day after she was charged with concealing the death of her 4-year-old son at the hands of her boyfriend, a 28-year-old woman has been charged with murder.

Crystal Valdez was originally charged only with child endangerment and attempting to conceal the murder of her son, Christopher Valdez. But her charges were upgraded Monday, assistant Cook County State’s Atty. Maureen Hughes said during a bond hearing on Monday.

A tearful Crystal Valdez appeared alongside her boyfriend Cesar Ruiz, 34, before Judge Donald Panarese, who set her bond at $750,000 Monday morning, charged with the murder of little Christopher Valdez. Ruiz, who was charged with first-degree murder on Sunday, was ordered held on $2.5 million bond.

Valdez — who was convicted just a month ago of a domestic battery of the boy, but was spared jail — gave a videotaped confession, admitting she’d spanked him twice in the week before he died, Hughes said.

She also admitted witnessing Ruiz beating Christopher on Thanksgiving and on Friday, the child’s birthday, Hughes said. Ruiz hit and kneed the child in the stomach repeatedly and Valdez saw him apply make-up to cover the bruises, the prosecutor added.

Ruiz gave a videotaped statement of his own, admitting he’d grabbed, spanked and hit Christopher several times, then covered the bruises with make-up, it’s alleged.

Valdez’s brother and sister-in-law found Christopher’s dead body wrapped in a blanket at his home in the 5100 block of South Trumbull on Friday after concerned relatives called and told them he had appeared at a Thanksgiving celebration with a swollen eye, Hughes said. Christopher had refused to eat dinner and had vomited, she said.

Confronted by her brother and sister-in-law at her home Friday, Valdez lied and claimed the children were not there, Hughes said. When they found the body, she yelled that Ruiz had done it, Hughes added.

Paramedics noticed the make-up used to conceal the injuries to Christopher’s face and arms, she said.

Caroline Glennon, an assistant public defender representing Valdez, said Valdez was a mom of four who had special educational needs as a result of lead poisoning as a child. She has split up with Ruiz, Glennon said.

Valdez wept and exclaimed, “I didn’t do anything” towards relatives in the gallery after the judge set her bond at $750,000.

The tattooed Ruiz gave no show of emotion as he was ordered held on $2.5 million bond.

Outside court, Ruiz’s sister Maria Castillo said she did not understand why her brother’s bond was higher than Valdez’s, given her history of violence against Christopher, or why Valdez was allowed to continue to raise the boy.

Valdez was convicted of domestic battery on Oct. 24 and sentenced to parenting classes and conditional discharge by Judge James Patrick Murphy. She admitted punching Christopher in July “because she was angry” and to using make-up to cover his injuries at that time, Hughes said in court Monday.

An Illinois Department of Children and Family Services investigation in August found that allegations of neglect in Valdez’s case were substantiated, DCFS spokesman Kendall Marlowe said Sunday, but allegations of abuse were not substantiated.

“Why the children were given back to her I have no idea — it’s beyond me,” Castillo said Monday. “It’s a tragedy.”

(The Sun-Times Media Wire contributed to this report.)

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