A woman serving a life sentence in the abduction and murder of Tori Stafford has been charged with assaulting another inmate, media reports suggest.

According to several published reports, Terri-Lynne McClintic got into an altercation with Amy McIntyre at the Grand Valley Institution for Women in Kitchener on January 30 and was charged with assault in early February.

She'll appear in a Kitchener courtroom via video link on April 26 to answer to the charge.

The relationship between McClintic and McIntyre, who are both serving life sentences, is not known.

McClintic, 21, pleaded guilty to abducting eight-year-old Tori Stafford from her Woodstock school on April 8, 2009 and killing her that same day.

She's been back in the headlines over the past few weeks as the Crown's star witness in the first-degree murder trial of Michael Rafferty.

Rafferty, McClintic's ex-boyfriend, is charged with first-degree murder, kidnapping and sexual assault causing bodily harm in connection with Stafford's death.

Though McClintic originally told police that it was Rafferty who delivered the fatal hammer blows to Stafford's head, she has since changed her story and has testified that she was the one who murdered Stafford.