Looking for information on Douglas Chisholm's in Manitoba, Canada

Hello, I am trying to find information about my Father's family who I believe was Chisholm in Manitoba. He was born Douglas Chisholm in 1929, had an older sister, but his parents both died in a car accident in 1929 or 1930 and he was adopted by the lady who ran the local Veteran's Hospital. That's about as much of the story as I know. If anyone can help with some information I would greatly appreciate it. Thank you!