Within a year, Steuer had received a minor guest-starring role on the television series Day by Day. In 1990, Steuer was cast as Alexander Rozhenko in the Star Trek: The Next Generation episode "Reunion". Although a number of young children auditioned for the role, Steuer was the only child able to sit still for the three hours it took for the make-up department to cast his Klingon facial prosthetics. The ability to be still for a long period of time won him the part. The producers of the series sought him out a year later to reprise the role. However, Steuer had only grown half an inch in height and, at six years old, did not have a deep enough voice. So the producers cast actor Brian Bonsall, who was more than two years older, as Alexander. Steuer later said he was very upset at the part being recast.