Jessica,
From the information on this website, the first option you might want to take is to find out about his daughter, Eileen Borebank (apparently his only child, from what the article states in this website under his biography). Perhaps she never married, and therefore had no progeny? You may want to contact a registrar in Winnipeg, Manitoba, to see if you can find information on John James Borebank or Eileen Borebank, giving specific dates, such as Eileen Borebank was born approximately in 1904 and apparently in Winnipeg, etc (seeing that JJ lived there with his wife, Isabel, during the time of their daughter's birth). Try this website link: winnipeg.ca/interhom/departments/ Perhaps that may lead you to some possible connection. Search for birth certificates, death certificates, marriage certificates, and e-mail someone giving the fundamental specifics of JJ Borebank and his daughter, Eileen, and what became of JJ in 1912, etc.
I wish you the best of luck in your search.