New York ( CNN ) -- Handcuffed to a bed and wrapped in a hospital blanket , a New York nanny accused of killing a sister and her toddler brother pleaded not guilty Wednesday to murder . In a case that has given many parents nightmares , Yoselyn Ortega was watching 6-year-old Lucia and 2-year-old Leo Krim at their Upper Westside Manhattan home in late October when police say she stabbed the kids to death . Their mother came home , police said , and found her children in the bathroom . She also saw the nanny stab herself with a kitchen knife , authorities said . `` This crime shocked and horrified parents around the city , many of whom entrust their children to the care of others both by necessity and by choice , '' Manhattan District Attorney Cyrus R. Vance said in a statement . `` My heart goes out to the family of those beautiful young children , and I hope that , with time , this family will heal . '' Wednesday 's hearing took place -- not in a courtroom -- but at Manhattan 's Weill Cornell Medical Center . Ortega , 50 , did not speak , and her lawyer entered her plea for her . The nanny is expected to undergo psychological evaluation , said authorities . She has been indicted and charged with first- and second-degree murder in both deaths . A native of the Dominican Republic , Ortega had been a naturalized U.S. citizen for 10 years . Her next court date is scheduled for January 16 .
Her next court date is scheduled for 50 , following a psychological evaluation . Marina Krim , January 16 , is accused of murdering Lucia Krim , 6 , and her brother Yoselyn Ortega , 2 . Police say that on October 25 , Marina Krim found her children dead in the their apartment .