The film's soundtrack featured Houston's signature song "I Will Always Love You." In the movie, Costner plays a former Secret Service agent who falls in love with Houston's character, a pop star he was hired to protect from a dangerous stalker.
Aretha Franklin and Stevie Wonder are expected to sing at Houston's invitation-only funeral service Saturday, while Houston's longtime mentor, record producer Clive Davis, also will give a eulogy, Houston's representative told the celebrity news Web site.
The funeral for the 48-year-old recording star, who died last weekend after a long battle with drug addiction, is to take place in the Newark church where she sang as a child and teen. Her death remains under investigation and officials have not yet announced what caused it.
"Whitney's family is devastated, but they're getting through it," People.com quoted an insider as saying. "Clive has been a complete rock for her family this entire time. He's been with her since the beginning, and he's been everything to them. They're leaning on him for emotional support. He talks to them hourly, and he's a very big part in planning her funeral. Clive has been a constant presence for them. They're thanking God for Clive."