cov-canuck

I hope someone here might be able to offer a bit of advice...

We're emigrating to Canada later in the year, but will first be spending about a month with my parents in South Carolina as a bit of a wind-down before starting the big house-hunting/job-hunting push in Canada. We want to send some of our belongings to them in advance of our arrival, since we don't have an address in Canada we can ship things to at the moment.

I'm not talking about much, just a couple of boxes of towels, crockery, photos, "personal effects", etc. (about 3-4 boxes total), which will be sent by courier. All items are in used condition, but fall under our category of "cheaper to ship than buy new"! Since I'm a returning Canadian citizen (and my husband is a landed Canadian PR), I know that I can declare the items when we cross the Canadian border, so not have to pay duty on them there, but how can I avoid paying customs duty on them when shipping them to my parents (if possible)?

Thanks in advance.