[Zairaa]

I've been to Canada twice, on a temporary resident visa. Once alone, when I was 16 and once with my parents when I was 17. I want to go this year on a Temporary resident visa, I'm 21 now. My sister and her husband (Canadian citizens) have sent me an invitation letter, along with their bank statement and employment letters). I'm planning to apply for it, I'm a student, Dependent on my parents.
Do you think my application would be rejected? I'm attaching my dad's share statement worth $35000. I have a return ticket.
I'm a Pakistani citizen.
Also how long will the visa process take?