Leonard Waynflete is a non-canonical character created for the 2009 ITV adaptation of Murder is Easy. He was the brother of Honoria Waynflete who had died some twenty years before the events in the episode. He only seen in flashback and on a photograph. Leonard Waynflete is portrayed by Julian Lightwing.
Honoria Waynflete also had a brother in the original novel but his name is not given and in any case what can be known about him from the text does not match the profile of Leonard here.