Rachel Prager, better known by her stage name Baby Blue, is a British rapper and singer from London, England. She is known for her work with singer Estelle and collaborations with John Legend, Madness, Sway, Shystie, Ms. Dynamite and Lady Sovereign. Baby Blue has a sound that fuses hip hop with grime, R&B and soul. In 2018, Prager-Riel became "Head of Music" at 7Wallace, Idris Elba's record label.