#9: Katherine Helmond as Mona Robinson
Mona Robinson was the show’s scene-stealer. Always quick with a joke or mischievous grin, she represented a kind of liberated spirit rare for TV grandmothers at the time. Mona constantly challenged conventions, supported Angela, and delighted audiences with her unapologetic love of adventure, romance, and bending the rules.
Helmond already had a career full of accolades, including widespread recognition from Soap. She entered Who’s the Boss? as a veteran performer, bringing gravitas to the sitcom. Her sharp wit and impeccable timing gave Mona a personality that was equal parts outrageous and endearing, making her unforgettable to fans.