A Queens woman has admitted to brutally beating her infant son more than a year after he was declared brain dead and taken off life support.

Prosecutors say Kiana Paez pleaded guilty to manslaughter Thursday in the death of 8-week-old Pablo. The child suffered a broken leg, broken ribs, a fractured skull and bleeding on the brain.

He was declared dead on April 24, 2008.

Paez, who’s 24, is expected to be sentenced to 19 years in state prison and five years’ probation on Oct. 22.

The boy’s death helped spur a city policy allowing newborns to be removed from homes if parents had other children taken from their custody.

Pablo’s older sibling had been taken from the same home a year earlier and placed in foster care.