Aaron Schaffhausen’s murder case will be back in court Friday, this time with lawyers arguing over how much the convicted killer should pay in restitution to his ex-wife, the mother of his three deceased daughters.

Prosecutors are asking that Schaffhausen, who is spending life in prison, be ordered to fork over $14,661.28 to make up for Jessica Schaffhausen’s expenses including medical costs, counseling services and lost wages.

A jury found that Schaffhausen was sane and responsible when he killed 11-year-old Amara, 8-year-old Sophie and 5-year-old Cecilia in the River Falls, Wis., home the girls shared with their mother in 2012. Prosecutors said he did it to get revenge on his ex-wife.

Defense attorneys argued in court filings that no restitution is due and that Jessica Schaffhausen is not a direct victim. They are asking prosecutors to produce paperwork showing her medical diagnoses, medications and reports documenting her inability to work in the months following the killings.

In addition, the defense alleges that after the murders Jessica Schaffhausen interfered with Aaron Schaffhausen’s ability to sell the house where she and the girls lived.  She objected because he would have profited from the sale, and after the house went into foreclosure it was dismantled.

“The mother cannot seek pecuniary damages and yet interrupt the ability of the defendant to incur pecuniary gains,” a defense attorney wrote.

Aaron Schaffhausen is serving three consecutive life sentences in prison for the deaths of the girls. It’s unclear whether he or the girls’ mother will appear at the hearing, scheduled for Friday morning.