Grammy-winning singer and actress Whitney Houston, 48, died Saturday in her Beverly Hilton hotel room, ending an astonishing career of superstardom that had been tainted, in recent years, by drug-related problems. News of Houston's death sent shockwaves through the music world on the eve of the 54th Annual Grammy Awards, known as "Music's Biggest Night."

All that is known surrounding the circumstances of Houston's death is that a member of her entourage found her unconscious in the bathtub of her room, CBS News reports. An autopsy was performed but its results, as well as that of a toxicology exam, are pending. Houston's exact cause of death will not be know until the results of these tests are determined.

Known for such hits as "The Greatest Love of All" and "I'm Every Woman," Houston was honored at Sunday's Grammy Awards by peers in the music industry still reeling from her death. The night's host LL Cool J began the ceremonies with a prayer for Houston and her family, and singer Jennifer Hudson performed a rendition of Houston's iconic ballad, "I Will Always Love You," from her bestselling and Grammy-winning soundtrack to The Bodyguard.

The niece of Dionne Warwick and the goddaughter of Aretha Franklin, Houston was music royalty who grew up singing in church. Bobbi Kristina Brown, 18, her only daughter with ex-husband Bobby Brown, was rushed to the hospital on Saturday and was treated for stress and anxiety.

Houston, who starred in The Bodyguard and The Peacher's Wife in the '90s, had recently completed work on a remake of the film Sparkle with co-star Jordin Sparks.

An outpouring of shock and grief — from colleagues and admirers around the world — flooded the press all weekend, with many making public statements online. Oprah Winfrey, who interviewed Houston in 2009, heralded the singer's talent and contribution to the world while mourning her loss. "To me, Whitney was THE VOICE," Winfrey tweeted Sunday. "We got to hear a part of God every time she sang. Heart is heavy, spirit grateful for the GIFT of her."

Watch Houston's iconic performance of the national anthem at the 1991 Super Bowl here:

Read more here:

Whitney Houston A Judge On 'The X Factor'? Yes, Please.

Amy Winehouse Post Mortem Inconclusive

Christina Aguilera Tributes Etta James At Funeral

Etta James Dies At 73