Sending packages from US to CAD

My sweet old grandma is a lifelong loyal FedEx customer thanks to my grandpas previous service flying planes for FedEx his whole life. She sent me a package last year from the United States to Ontario and I ended up having to pay duties/taxes on it because she forgot to declare the value/description at the time of shipping. I paid it without telling her about the issue because I felt bad and she was just trying to do a nice thing for me. Well now she has sent a gift again, this time she declared the value/description at shipping etc and I STILL got a bill $100+ in the mail for duties/taxes. I am furious. Is there any way I can avoid these bills in the future? She likes sending me physical presents in the mail because she is old school and I feel terrible asking her not to send me items anymore… but I can’t afford to pay these large fees every time I recieve a package. Any solutions??? I did not think it would be an issue having my family send me care packages/gifts from the US as long as we declare the value of the items just like crossing the border via car? But clearly I am missing something