Yoselyn Ortega's sister shows a picture of the nanny accused of killing two children. AP Images The nanny accused of stabbing two young children to death on the Upper West Side was reportedly angry the family asked her to do housework in addition to her babysitting duties.

Yoselyn Ortega allegedly stabbed 6-year-old Lucia Krim and 2-year-old Leo Krim to death last week and then tried to kill herself.

When she was questioned by police after the slayings, Ortega told police she was angry the family asked her to do housework in exchange for earning extra money — something the family did because they believed they were helping their cash-strapped nanny, The Daily Mail reported, citing an unnamed law enforcement source.

"She said something like, 'I'm paid to watch the children, not clean up and do housework,'" the law enforcement source told The Daily Mail.

Ortega was in a medically-induced coma following the stabbing and was recently woken up to speak with police.

The Krims were also reportedly concerned with Ortega's performance and told her she needed to improve or would be fired.

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