CHICAGO (CBS) — Cook County Public Guardian Robert Harris is criticizing the Department of Children and Family Service’s handling of a case involving a Southwest Side boy killed on his fourth birthday.

He says Christopher Valdez shouldn’t have been returned to his mother last month – after she was convicted of abusing him.

Prosecutors allege Crystal Valdez helped her boyfriend, Cesar Ruiz, beat Christopher to death at their Southwest Side home Friday.

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A tearful Crystal Valdez appeared alongside her boyfriend Cesar Ruiz, 34, before Judge Donald Panarese, on Monday who set her bond at $750,000, charged with the murder of 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, prosecutors 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, prosecutors said.

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