To answer your question, yes you parents will have to have a computer at the location of the Slingbox to set the unit up on. The computer has to be on the same network as the Slingbox to set up the network connection to the Slingbox.
The new Slingbox M1 that is only supported here in the United States can be setup at the home location from an iPhone, iPad, or Android Phone with the current SlingPlayer software installed on it. But keep in mind that that software is separate from the purchase of a Slingbox.
Sling Media Moderation Team