Can the bank cancel an approved mortgage if they see you get a car loan?

My dad just got approved by the bank today for his mortgage on a house he purchased. He said that he will cosign with me so that I can purchase my car. But now his real estate agent said that if the bank saw that he has a car loan before the move in date of August 5th they can cancel the approval, is that true? Or can he help get me a car next week? I am in ontario Canada.

Read more: Can the bank cancel an approved mortgage if they see you get a car loan?