Cindy Anthony, who granddaughter’s death led to one of the most infamous murder trials in modern U.S. history, has said for the first time that she believes her daughter Casey Anthony is mentally ill.

Casey was acquitted of murdering her daughter following a sensational 2011 murder trial, but has never escaped a cloud of suspicion, given that the mystery of her two-year-old daughter Caylee Anthony’s death was never solved. Further, Anthony was convicted of lying to police about the circumstances of her daughter’s disappearance.

While Cindy Anthony has been publicly supportive of her daughter in the past, both she and her husband appear to have abandoned any hope for a healthy relationship with their daughter–unless she gets help.

The Orlando Sentinel reports that George and Cindy Anthony will appear on Crime Watch Daily on Monday, and the show has released preview footage of the interview.

“Casey, be true to yourself, start being honest with yourself, and own everything. Quit putting blame on everybody else,” Cindy Anthony says.

“I think Casey is mentally ill,” she says.

It is unclear if Cindy is implying she knows Casey is responsible for Caylee Anthony’s death, but she does later say in the interview that she believes Casey, who reportedly suffers from seizures, may have had a seizure at the time of the toddler’s death.

George Anthony also sent a harsh message to his daughter:

“Stay away. Stay away from me. If she wants a relationship again with her mom, she’s got a lot of explaining to do, but I don’t want to hear it no more. I don’t want to see her.”

The interview will air on Crime Watch Daily with Chris Hansen, which is broadcast on numerous TV stations throughout the country on Monday at 9 a.m.

[Feature photo: Associated Press]