Together gospel singer Cece Winans and Whitney Houston recorded one of the most memorable songs about friendship, the track “Count on Me” from the Waiting to Exhale soundtrack. Now, hours after finding out her friend passed away, Winans says she is shocked. “I have no words to express how I feel,” she says in a statement to

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“Whitney was not just a friend but a sister and I am going to miss her voice, her humor but mostly her friendship,” she adds.

Through their decades-long friendship, it wasn’t uncommon for Houston to drop in and sing at a BeBe and CeCe Winans concert, after she introduced herself to the pair at an awards show in 1987. What made them relate to each other? Being raised in the church. In fact, the first time CeCe Winans heard the pop queen’s voice, she told PEOPLE, she was certain Houston was a gospel singer.

Winans stood by her friend even through her battle with drug abuse. “I love her and I’m praying for her,” she said in an interview in 2010.

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“Please keep [Whitney’s] family in prayer, and the best way to honor her is to be reminded that tomorrow is not promised to any of us, so love God and love each other,” adds Winans.

Watch Houston and Winans sing their classic duet “Count on Me” from the Waiting to Exhale soundtrack.