Just want to point out a few things:
1) even if he gets a visitor visa, he cannot work in Canada
2) he will not get any coverage in Canada on his treatement on visitor visa, so if he wants to get any treatment or thraphy, he should do so in Italy
3) Since you have been on welfare, and now you are working and off the social assistant, you should call the provincial organization and make sure they take you off the list
4) Why do you need dead certificate and police background info of your dad? I think you only need this kind of document for the applicant. Not the sponsor. You only need your birth certificate/passport/citizenship certificate as your ID.