For parents and grandparents, I would say 12 months, because they are not in Canada. For whatever reason, it takes 51 months or 36 months. I'm just throwing this number out there, because I think 12 months is something I can live with. I sponsored my own mom, and it took me three years. It's ridiculous, because there is no reason for it to take that long when they have all the paperwork and everything is there. The downside of this is that, when you call Immigration, they say, “Well, you haven't reached your maximum processing time; you need to wait” or “We don't have any more information; you'll just have to wait.” That is not an answer.
On November 1st, 2016. See this statement in context.