thats odd. I just accessed it? email me and I will send you the page. I think they can do a transit visa for so many hours.(90 "?) look further into the site I sent you :)
<em>edited by SueB on 05/04/2011</em>
There is a mulitiple entery visa ($$$) that is valid for 6 months, with stays as long as 15 days. The standard visit visa does not allow you to re-enter. It will be cancelled at the border/airport/port.
You could sponser your family for a residence visa, and then cancel them when they are done visiting. As, a Canadian, when you cancel your visa you will need to wait 30 days before re-applying for a new visa. You will be denied entery at the airport w/oa proper visa. HTH