Singer recalls time she spent with the late pop icon on the set of 'Sparkle'
Singer endured four tryouts for part of daughter
'Celebrate' is a duet with former 'Idol' winner Jordin Sparks
Movie set for August release
Inside the singer's meteoric rise, chaotic life and tragic final days
Late singer recorded new songs for 'Sparkle' remake
Singer in talks to star in musical with Jordin Sparks