This could get really out of hand quickly, but this is for diva songs that sound a lot like other songs, or diva songs that sound significantly influenced by other songs or with very similar sounding elements.
Janet
FUNNY HOW TIME FLIES - Michael's THE LADY IN MY LIFE
SOMEDAY IS TONIGHT - the chords at the end of each chorus are identical to the ones found in Pet Shop Boys' WEST END GIRLS.
WHAT'LL I DO - The Rolling Stones' SATISFACTION
Madonna
THE LOOK OF LOVE - Phil Collins' ANOTHER DAY IN PARADISE (really similar chord progression)
MATERIAL GIRL - very similar bassline to The JAcksons' CAN YOU FEEL IT
LIKE A VIRGIN - Michael Jackson's BILLIE JEAN
BORDERLINE - Stephanie Mills' NEVER KNEW LOVE LIKE THIS BEFORE
HOLIDAY - Change's LOVERS HOLIDAY
EXPRESS YOURSELF - The Staples Singers RESPECT YOURSELF
Mariah
EMOTIONS - Cheryl Lynn's GOT TO BE REAL
Janet
FUNNY HOW TIME FLIES - Michael's THE LADY IN MY LIFE
SOMEDAY IS TONIGHT - the chords at the end of each chorus are identical to the ones found in Pet Shop Boys' WEST END GIRLS.
WHAT'LL I DO - The Rolling Stones' SATISFACTION
Madonna
THE LOOK OF LOVE - Phil Collins' ANOTHER DAY IN PARADISE (really similar chord progression)
MATERIAL GIRL - very similar bassline to The JAcksons' CAN YOU FEEL IT
LIKE A VIRGIN - Michael Jackson's BILLIE JEAN
BORDERLINE - Stephanie Mills' NEVER KNEW LOVE LIKE THIS BEFORE
HOLIDAY - Change's LOVERS HOLIDAY
EXPRESS YOURSELF - The Staples Singers RESPECT YOURSELF
Mariah
EMOTIONS - Cheryl Lynn's GOT TO BE REAL





