NEW YORK (CBSNewYork/AP) – A New York City man will spend 20 years to life in prison for killing his 5-year-old son and sickening his 7-year-old daughter with poison-laced pizza.

After learning that his ex-wife was seeing another man, Leonardo Espinal took it out on their children in November 2012 by tainting their pizza with rat poison, Bronx District Attorney Robert Johnson said Thursday after the sentencing.

The little girl, Mia, threw up after eating the pizza. When her brother, Steward, soiled himself, their father took him into the bathroom.

Espinal’s stepmother called 911. Police broke down the bathroom door. Steward was in the bathtub, dead from a combination of the poison and being submerged in water.

“My beloved angel,” the children’s mother, Rosaura Abreu, said in a victim impact statement that was written in Spanish, translated into English and read by a prosecutor in court.

“I will never forget the last time I saw my little son. — He was radiant, happy, content and followed me all around the house.”

“When it was time for me to leave, he followed me to the door and I knelt down to talk with him. It’s as if my heart knew that it would be the last time I would see him alive.”

Steward told his mother that he loved her. They hugged and she said “that I loved him from the bottom of my heart, more than own life.”

After the crime, Mia suffered anxiety attacks at the mere mention of returning to the apartment. “She never wanted to sleep in the same bed where she slept with her Steward, protecting him from monsters,” their mother said.

Therapy has helped them, but is by no means a cure-all.

“Mia suffers a great deal when she goes to parties, when she goes to bed, when she plays with other children, when she sees photos of him, when she sees another boy the same age as him, when she sees me sad because she knows I am thinking of him,” Abreu said.

Espinal pleaded guilty last month to murder and attempted murder.

“All we can do,” said Abreu, “is take it day by day.”

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