My Canadian passport has expired, which wasnt a big deal for me because I can travel on my US passport. Now my husband is filling out the PR application and it wants my passport number. Is it a big deal that my passport has expired?
Not having a Canadian passport doesn't affect your ability to sponsor. I'd suggest putting the expired Canadian passport details in (because proof of your citizenship is actually what matters for the sponsorship, not what passport you travel on), but you could also include an additional sheet explaining the situation, and listing your US passport details, in case there is some other reason they need a current passport.