Whitney Houston's sister-in-law has said she feared that drugs would end the singer's life in an interview with Oprah Winfrey to be broadcast this Sunday.
In a partial transcript Patricia Houston said she would be "kidding herself" to say otherwise.
Patricia Houston, who was her sister-in-law's manager, was asked if she thought drugs would end up "taking" Whitney Houston. The "handwriting was kind of on the wall," she replied.
The pop star was changing how she lived, Patricia Houston said, and "it wasn't about substance abuse or anything like that relative to the ... latter days or anything like that."
"It was just more of a lifestyle. I was afraid for other things," Patricia Houston said. "I saw her chasing a dream, you know, looking for love in all the wrong places."
Bobbi Kristina, Whitney Houston's daughter with singer Bobby Brown, also was interviewed for the episode of "Oprah's Next Chapter" airing 9pm. EST Sunday on Winfrey's OWN channel. The 19-year-old discusses how she wants her mother to be remembered, OWN said Thursday.
The troubled 48-year-old singer, who had battled years of addiction, was found dead in her room at the Beverly Hilton Hotel in Los Angeles hours before she was due to attend a star-studded party downstairs.
Two bodyguards, a hairdresser and stylist were believed to have been in the singer's room at the time and discovered her body, with her head under the water, after becoming concerned that she had been in the bathroom for more than an hour.
Prescription drugs, but no illegal drugs, were found in the suite. Houston was known to take Xanax, a drug to ease anxiety which can cause drowsiness, before performances. Anti-anxiety drugs Valium and lorazepam were also believed to have been found.
An autopsy will establish whether the singer fell asleep and drowned, died from an overdose, or from some other cause. Paramedics tried to resuscitate her for 20 minutes but she was pronounced dead at 3.55pm (11.55pm GMT) on Saturday.
On Thursday, two days before her death, witnesses said Houston had displayed erratic behaviour, including doing handstands by the Beverly Hilton Hotel pool, and wandering aimlessly around the lobby.
Later that night she was seen looking dishevelled at a Hollywood nightclub, drinking tequila, and video showed her performing there briefly in a faltering voice. On Friday night she was seen "partying hard" in the hotel bar with friends.
She had been attending rehearsals for the Grammy Awards, giving vocal tips to singers Brandy and Monica. Her behaviour there was also described as erratic, and she was said to have been sweating profusely, and alcohol was smelled on her breath.
The singer's mother, Cissy Houston, spoke to her on the telephone half an hour before she died and Miss Houston was said to have been looking forward to the party. The singer's 19-year-old daughter Bobbi Kristina was at the hotel.
As news of the singer's death spread tributes poured in from prominent entertainment figures and fans across the world, with fellow performers calling Miss Houston a "legend" and an "icon."
Music's biggest night the Grammy Awards, where she had been due to appear on Sunday, were quickly transformed to include tributes including one to be sung by Jennifer Hudson.
Houston's godmother, the soul singer Aretha Franklin, said: "I just can't talk about it now, It's so stunning and unbelievable. I couldn't believe what I was reading coming across the TV screen."
Mariah Carey said she was "heartbroken and in tears over the shocking death of my friend," and Dolly Parton said: "Mine is only one of millions of hearts broken."
From the mid-1980s to the late 1990s, the gospel-trained Houston was one of the world's bestselling recording artists. She mesmerised audiences with her powerful vocals, released seven studio albums and sold 170 million CDs, singles and videos.
Songs like "I Will Always Love You" and "Saving All My Love" became global hits which were endlessly attempted by lesser singers at karaoke events everywhere. She also starred in movies including "The Bodyguard" with Kevin Costner.
But her career began to unravel as she battled drug addiction, spent various spells in rehab, and embarked on a tumultuous 15-year marriage to "bad boy" singer Bobby Brown.
In an infamous 2002 interview, with Brown by her side, Miss Houston told ABC's Diane Sawyer: "The biggest devil is me."
She confessed to abusing cocaine, cannabis and pills, but famously denied using crack cocaine, saying: "I make too much money to ever smoke crack.
Crack is walk." Her once pristine voice became raspy and hoarse, she was unable to hit the high notes of her prime, and record sales nosedived.
In 2007 her marriage to Brown ended and two years later she made a comeback, releasing a new album after seven years. But as she went on tour many fans were unimpressed and some walked out.
The singer had recently finished work on a film called "Sparkle" which will see her posthumous return to the big screen in cinemas in August.
Ironically, the film focuses on a group of musical sisters whose lives are blighted when one of them becomes addicted to drugs and sees her life spiral out of control.
On the night she died Miss Houston had been due to attend a lavish, star-studded annual pre-Grammy party hosted by her long-time mentor, record producer Clive Davis, at the Beverly Hilton.
A surreal scene unfolded at the hotel as the party continued while Miss Houston's body remained in her room on the fourth floor, which was sealed off with yellow police tape.
Entertainment reporters had been waiting to interview her in a room downstairs when they were informed she was dead.
Guests at the hotel bar watched news of the singer's death unfold on a television screen while others in the lobby were cheering the arrival of party guests, including Britney Spears, to the red carpet.
At a service entrance to the hotel a van marked "crime lab" waited. The body was eventually removed on a gurney after midnight through a back door.
At the party an emotional Mr Davis told the stunned celebrity audience: "I am personally devastated by the loss of someone who has meant so much to me for so many years.
"Simply put, Whitney would have wanted the music to go on and her family asked us to carry on."
Tony Bennett performed a tribute. Television personality Larry King, who was at the party, said: "Her remains are still in the hotel. It's really sad."
Kelly Osbourne, the reality television star and singer, decided not to go to the party. She said on Twitter: "Not going to any pre-Grammy parties as I don't feel it is appropriate."
Speaking at the hotel Lieutenant Mark Rosen of the Beverly Hills Police told The Daily Telegraph that a member of Miss Houston's entourage found her and called hotel security. The hotel called emergency services and paramedics arrived a few minutes later. He said there was no sign of foul play.
Bobby Brown, who was performing in Mississippi, told the crowd there: "I love you Whitney. The hardest thing for me to do is to come on this stage."