My wife and I would like to invite my sister from south Africa this summer. My sister is 22years and in third year in university in south Africa and does not work. My uncle pays her fees and is her guardian back in south Africa. My wife is a citizen and I am a PR, we both have good jobs and earn $100,000 a year with 3 rental properties and we will be fulling sponsoring her trip. My question is, is the third year in University proofs enough ties to show my sister will go back after her visit? Does my uncle have to prove funds or anything though he is not the one sponsoring? What are the chances of my sister getting the visa especially she has no travel experience?