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Nanny charged in stabbing deaths of two children on New York's Upper West Side

Carlo Allegri / REUTERS

A girl looks at a makeshift memorial left outside the Krim family apartment in New York on Oct. 28.

NEW YORK -- Police say they've charged an Upper West Side nanny with murder in the stabbing deaths of two young children under her care last month.

Yoselyn Ortega, 50, was arrested and charged with two counts each of murder in the first and second degrees in the stabbing deaths of two children in her care, Lucia Krim, age 6, and her 1-year-old brother, Leo, on Oct. 25.

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Leo's second birthday would have been Oct. 30.

Ortega was recuperating from knife wounds to her neck at New York-Presbyterian Hospital, where she had been under police guard since the stabbing deaths.

She agreed to speak with NYPD detectives Saturday afternoon from her bedside, and was formally arrested and charged after 6 p.m.

A third sibling was with their mother when the killings happened. The mother returned home to discover her children dead and Ortega bleeding.

Ortega remains hospitalized under police guard. She worked for the Krim family for two years. 

Jonathan Dienst is WNBC's chief investigative correspondent. This article includes reporting from The Associated Press.

The New York nanny who police say fatally stabbed two children in her care was reportedly enduring financial problems and seeking professional help. NBC's Mara Schiavocampo reports.