‘NIGHTLINE” anchor Terry Moran will interview the maternal grandfather of Virginia Tech killer Seung-Hui Cho.

It is the first time a member of Cho’s immediate family has agreed to talk.

On tonight’s “Nightline,” Moran will profile Cho’s history of mental illness and focus on the findings of a panel of experts who are expected to release a highly-anticipated report today.

In the interview, Cho’s grandfather, Hyang-Sik Kim, talks about the family’s agony following Cho’s bloody rampage and how the troubled youth had been a focal point of worry since he was a child.

“He never came up to me or called me Grandpa,” Kim says. “As a child, he never hugged.”