@swittie ...
To add to what @JeffCampbell has stated, Canvas does not really have e-mail. There is a Canvas Inbox within the user interface, but it's not the same as e-mail. The Inbox is a place where students and instructors can send messages to each other as long as they are enrolled in the same class(es). The Canvas Inbox is not e-mail...in that students cannot e-mail their friends and family from within the Canvas environment because they are, most likely, not enrolled in those same class(es). By the same token, friends and family cannot e-mail people inside of Canvas. It's really a messaging tool within Canvas for instructors and students to communicate with each other. Hopefully there are other ways (such as Outlook) that can be used to contact the parent. Good luck to you!