Hello everyone, i am applying for visitor visa, the reason is attending dental congress in Vancouver and my travel history is good and my wife too is attending tge same congress with good travel history. The organization will send invitation letter and the congress is 5 days, at the same time my sister is PR in Manitoba and can offer me an invitation to apply for visitor visa. The question is it better two apply with two letters (the congress letter and my sister letter) or it's better to apply with one letter