There were 3 Condos brothers, dancing only in pairs live and on film:
Frank Condos and
Nick Condos from 1929-1933, then Nick and
Steve Condos thereafter. "Harry" is the invention of a Playbill for the 1930 appearance of Frank and (presumably) Nick on Broadway. Any book or website that claims Frank and/or Harry were dancing on film (after Frank's appearance in The Midshipmaid (1932)) were likely sourced from misinformation. All film credits after '32 that list Condos Brothers refer to the brothers Nick and Steve. Both Nick and Steve have solo credits as well.