Kelly Rowland can command an audience on and off the stage. The “Motivation” songstress was secretly filmed by her assistant singing in the shower. Kells, who kicks off her tour with Chris Brown later this month, showed off her vocal chops with a soaring rendition of “Part of Your World” from Disney’s The Little Mermaid. “I’m a black mermaid,” declared Kelly after realizing she was being taped. Those hoping to get a peek of Kelly’s other assets are out of luck.