Mercedes Polanco worked as a production assistant for Sesame Street from Season 10 to 16. She is credited for the same role for the specials Christmas Eve on Sesame Street and Don't Eat the Pictures.
During her time on the show, Polanco was frequently seen as one of the volunteer caretakers at the Day Care Center (including Episode 1210, 1288, 1440, 1646, and 1731). Unlike other onscreen cameos by staff members, she was deliberately listed among the cast in scripts set at the center. She appeared outside the cay care setting in Episode 1436 (participating in the garage sale), and later made another cameo appearance in Episode 3734.