I should perhaps have started with these 2 marriages b/c mother's maiden name should help you to be sure that Peter and John in the 1911 Census are indeed your folks.
These are the marriages of a son and daughter of Peter.
Mary Munce Black, 17 (with the written consent of her mother), Spinster, a Clerk, b. Scotland
Of 84 Kenwood Ave,
Parents Peter Black and Annie McGill
to
Thomas Edward Marlow, 23, Bachelor, a Chauffeur, b. Worcestershire England
Of 24 Lonsdale Rd
Parents Edward Marlow and Sophia Brownson
At Toronto 02 Apr 1917
One witness was Jno Black of 98 Kenwood Ave
Bouncing screen ....will continue