Hi,
There is a baptism listed in the Ontario, Canada, Catholic Church Records (Drouin Collection), 1747-1967 on Ancestry. It states John Wm. born 17 Feb 1919 to Wm John Corcoran and Anna Scott in Port Arthur. Baptism 23 June 1919 at St. Andrew's.
Godparents: Emmett Corcoran by proxy, Stella Redden.