Authorities went to the house on Girdle Ridge Road in Katonah shortly before 9:30 p.m. Saturday after receiving a 911 call.
On Sunday, a police presence was among the few signs of activity at the home of the young victims.
Their house is tucked away in one of Westchester County's most exclusive neighborhoods.
It was a house of horrors for 9 and 7-year-old Annabelle and Maive Kelly, who police say were stabbed, numerous times, by their aunt.
She was identified as 39-year-old Lisa Turkki of East Syracuse, New York. Turkki was charged with two counts of assault.
She's the sister of the victims' mother, Eva Kelly.
Ms. Kelly and her husband reportedly left the girls in Ms. Turkki's care as they went out for the evening.
Police say it was the suspect who called 911 after the attacks.
Lt. Jeffrey Dickans said Monday that the girls, Maeve and Anabel Kelly, were both conscious and talking when they were found at their Katonah home.
He said two kitchen knives believed to be the weapons were recovered at the scene.
He said the suspect, Lisa Turkki, sustained a minor injury to her leg. It appeared to be self-inflicted.
A hazardous materials cleaning truck spent hours at the home, suggesting the blood and brutality of the crime.
The little girls were brought to Westchester Medical Center with stab wounds to the legs and back, according to hospital sources.
The injuries are not said to be life-threatening, but sources say both girls spent several hours in surgery.