First Look: Oprah's Next Chapter with
Cissy Houston

As the one-year anniversary of Whitney Houston's death nears, her mother, Cissy Houston, is sitting down with Oprah Winfrey for her first tell-all interview. In conjunction with the release of her new memoir, Remember Whitney, the gospel singer, 79, clears up the many rumors that still surround her late daughter.

Opening up about Whitney's drug use, her tumultuous relationship with ex-husband Bobbi Brown and serious concerns for granddaughter Bobbi Kristina, Cissy also recounts the heartbreaking moment she learned of the superstar's passing.

"My son [Michael Houston called me and he was screaming, 'Mom, Mommy. Oh god,'" she said of the phone call she received Feb. 11, 2012. "I said, 'What's wrong?' He said, 'Nippy. Nippy,'" using the family's nickname for Whitney.

"I said, 'Is she dead?' And he said, 'Yeah, Mommy, she's dead' . . . And I don't remember too much else after that."

The "Greatest Love of All" singer was found dead in her hotel room at the Beverly Hilton at the age of 48. The Los Angeles Country coroner's office reported her cause of death to be drowning and the "effects of atherosclerotic heart disease and cocaine use."

Cissy's interview on Oprah's Next Chapter airs Jan. 28 at 10 p.m. EST on OWN. Watch the clip now.