A woman stabbed her 79-year-old mother to death with a kitchen knife after the two argued over the daughter's ongoing medical problems, police said Tuesday.

Suzan Grossman-Kerner, 56, was arraigned Tuesday on a murder charge after the death of her mother, Irma Grossman, a day earlier. Grossman-Kerner's attorney, Todd Greenberg, said she was very distraught.

"She is an attorney and is very upset and a very decent person despite what happened here," he said. "She has a mental illness and we will deal with this within the court system."

Nassau County police said Tuesday at a news conference that Grossman was a "loving grandmother and neighbor." The daughter went to the mother's home on Monday, and the two argued, with Grossman-Kerner becoming enraged and attacking her mother, police said. She then called police and reported her mom had been assaulted. She was later taken into custody.

It's not clear how many times Grossman was stabbed. An autopsy was being performed. A weapon was recovered.

Grossman-Kerner has no prior arrests and is the mother of three college-aged children. There had been no calls of domestic violence to her mother's home before the attack, police said.

Grossman-Kerner's attorney said she has a prior psychiatric history, "a very serious psychiatric history and most likely that history will enter into the defense of this action," Greenberg said.