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Five months after the death of her brother Michael, Janet Jackson is speaking out for the first time about everything from the day Michael died to why she thinks Dr. Conrad Murray is responsible for the King of Pop's death.

"He was the one that was administering," she told ABC's Robin Roberts in an interview airing Wednesday. "I think he is responsible."

Meanwhile, Janet recounts the day Michael died.

"I was at my house in New York. You know, another day. Another morning. And I get a call ... [my assistant] said, 'Your brother's been taken to the hospital. It's on CNN right now,'" she told Roberts. "I called everyone. There's a line busy or -- someone wasn't picking up. I spoke to mother. I spoke to Tito. I spoke to my nephew Austin. I spoke to my sister La Toya."

Janet goes on to say Michael is constantly on her mind.

"It's been a tough year," she said. "You have your days where it's just really -- it's hard to believe. And a day doesn't go by that I don't think about him."