Liam Neeson sat down with Anderson Cooper for an upcoming "60 Minutes" interview to talk about the death of his wife, Natasha Richardson, and how he is coping five years later.

Richardson passed away in March 2009 after a ski accident that resulted in severe brain trauma at just 45 years old, and Neeson explained, "[Her death] was never real. It still kind of isn't."

He recalled when she was on life support and said, "I told her I loved her, said, 'Sweetie, you're not coming back from this, you've banged your head … she and I had made a pact, if any of us got into a vegetative state that we'd pull the plug.'"

Neeson says that he decided to keep Natasha on life support for a short period of time so that friends and family could say goodbye, and then donated her heart, kidneys, and liver.

The full interview with Liam Neeson airs on CBS this Sunday at 7 p.m. ET.