NEW YORK (CBSNewYork) — A jury on Wednesday found a former Upper West Side nanny accused of killing two kids in her care guilty of murder.

The jury spent two days deliberating before convicting Yoselyn Ortega on two counts of first degree murder and two counts of second degree murder in the stabbing deaths of 6-year-old Lucia Krim and her 2-year-old brother Leo in 2012.

The victims’ father, Kevin Krim, sobbed in court as the jury read their verdict. He embraced two alternate jurors sitting next to him and mouthed “thank you” to the jury as the left the courtroom, CBS2’s Hazel Sanchez reported.

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The former caretaker sat quietly as the judge read out the four guilty verdicts.

“There were raised voices and a lot of tears but I think we all feel good that we addressed all of the issues and fairly addressed everything that was presented to us,” juror David Curtis said following the verdict.

Prosecutors claimed Ortega acted out of anger against the Krims, particularly the children’s mother, for allegedly over working her. They alleged the murders were planned and said Ortega knew the consequences of her alleged actions.

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“Every stab, every slash, each one had a purpose. And that purpose was to end the lives of those children,” said Assistant District Attorney Stuart Silberg.

Defense attorneys argued the 55-year-old suffers from severe psychosis and depression and heard voices telling her to kill the kids.

“The reason for the defendant’s actions lay within her delusional mind. The lack of the defendant’s apparent motive is the hallmark of her mental illness,” said Ortega’s attorney Valerie Van Leer-Greenberg.

Jurors speaking after the verdict say they were split on their decision and coming to an agreement was not done lightly.

“We feel we had a charge and an obligation as they say you’re innocent until proven guilty,” juror Alexis Reyes said. “I think we feel great in the decision that we rendered.”

Jurors add they developed an undeniable bond with each other after experiencing the six-week murder trial, and they wanted to express their sympathy to the Krim family for all the pain they’ve endured.

“We are truly sorry for your loss and we hope this helps in the process of beginning to move forward,” Curtis said.

The victims’ parents released a statement Wednesday night:

This process has been very challenging for us, but it has also reaffirmed our love of New York: a city that Lulu and Leo loved dearly. We got through this trial because of our family, our friends, our fellow New Yorkers and the loving memory of Lulu and Leo’s lives.

The Krims say they’re channeling their pain into an initiative, named after their children, pushing for legislation that makes falsifying references on job applications for caregivers a crime.

Ortega is due back in court for sentencing next month, where prosecutors say they’ll ask the judge for a sentence of life in prison.