Brother William Mark Reidy was an Irishman who came to Australia at an early age and immediately demonstrated his many talents which resulted in his being involved in school administration for most of his teaching career. He spent twenty-three years at Terrace and for sixteen of these he was Headmaster on four occasions.

He was a man who did not suffer fools gladly and expected every boy to be a Terrace man through and through. While encouraging students in the classroom to work to their potential he could be seen regularly on the playing field urging the rugby players to ever greater efforts.

Brother Reidy was noted for the strength of his character, a trait he attempted to inculcate in those he taught. He enjoyed the warm friendship of scores of prominent business and professional men in Brisbane whom he had educated at Terrace.

He died in Sydney in 1962 at the age of eighty-three but because of his strong Queensland associations he was buried in the Brothers' plot at Nudgee Cemetery.