A direct descendent can get the birth certificate from the government.
Also, the plot owner will be listed at Mt Pleasant Cemetery and may be a relative.
Cemetery should have name of informant.
Funeral parlour would have informant.
I was thinking he may have been abandoned at the school but it was a government place and looks like the pupils were bussed there.
Does Sunny View have list of pupils.
McMaster University Archives have a David Edgar Freeman Fonds 1952-2012.
Source of acquisition: bequest from David Freeman's estate.
May be something in those.
What was in his will?