Transcript for Celine Dion Opens Up About Final Moments With Husband
We'll switch gears to that powerful exclusive with Celine Dion. She sat down with ABC's Deborah Roberts and good morning to you, Deborah. You have all of that for us. Reporter: Good morning, Michael. Yeah, I do. It has been a devastating time for the superstar singer. Not only losing the love of her life, but also the man who managed her career for 30 years. But one thing is pretty clear after meeting Celine Dion, her husband not only prepared her for, you know, going on the stage but he prepared her for one more act, a life without him. Last time I took that step with you. I know. We were three. I know. How are you? I'm very well. How are you. Okay. It was last spring when Celine Dion joined us on this stage with her beloved Rene who was in the retched throes of his cancer battle. The end came just four months ago, two days shy of Rene's 74th birthday. When I saw you last time you were bracing yourself. You were beginning to talk about the end. Did it still come as a shock? Because even when you're expecting it you kind of never expect it. I think I was more in shock when I did talk to you the last time, because I saw him suffer and that is the worst. Today for me it's like I don't live with him physically, but I live with him inside of me. Reporter: Her husband of 21 years slipped away quietly in the early morning hours of January 14th. I started to talk to him and I said, you know what, I want you to just go in peace. I want you to not worry. You were worrying for my career. You were worrying for the children. You were worrying for everything. It's enough. I promise you we're going to be okay. You left me now with enough good memories of you to share with my younger brothers. Reporter: The couple's sons 15-year-old Rene Charles and 5-year-old twins Nelson and Eddie now adjusting to life without their father. Every night we kiss him good night. Eddie starts, two fingers, one finger and he said love you papa so much, happy Easter, happy Halloween so Nelson goes and repeats almost the same thing but he adds more stuff and then I do the thing too and I said good night my love. You lost your brother a couple of days later. My brother passed away of pretty much the same cancer as him died on Rene's birthday and I said to myself, for his birthday, my husband came and got my brother because my brother was too weak to fly on his own. âª Reporter: Did you ever say what would Rene do? I think we all do. Do you think Rene would think that this song is appropriate but after a while am I going to have signs all the time or do I have to make decisions as a woman, as a mother, as an artist? Are you ready for that? Do I have a choice? You're never ready for something like this to happen, even though you expect it, when it hits you, you're not prepared. Reporter: Yet weeks later Celine is back on stage in keeping with her husband's wishes. He would be overhere watching the whole show. Reporter: Is there any one song when you sing it it's all about you and Rene? Whether I sing "The show must go on" because when I was sick, when he was sick, he always said, the show must go on âª the show must go on âª Reporter: He gave me a lot of strength and you know what, I'm at peace. The show must go on. A mantra for this couple. Celine is going to sing that song again at the billboard music awards. She accepts a bittersweet honor. She will be doing so for the first time without her husband by her side. So open and so honest with you and she's so strong. She really is. That was a powerful -- That was the power, I think, her strength. She wasn't falling apart. She can't fall apart but her husband prepared her. He knew this was happening. He wrote notes. He gave her instructions. They talked a lot so she knew what she needed to do and she's got a concert tour coming up. The show is going to go on. There every step of the way. Very strong woman. You can watch Deborah's entire interview with Celine Dion tonight on "Nightline" right here on ABC.
This transcript has been automatically generated and may not be 100% accurate.