Is it illegal to open someone else's mail in Canada?

I am in the middle of a separation and have moved out of the family home. I changed my mail address, however some mail has still gone through. My kids tell me that my ex is first night my mail.
Best Answer:

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Yes, it is illegal to open somebody else's messages, but it is not illegal to open your mail. Since your husband is exit YOUR mail, and not somebody else's mail, I am afraid there is zilch you can do about it.

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