I read a random article on Daily Dot, which included a (painful to get) spoiler for season 10, just out in the open. I wrote to them, and they said that since the sentence itself mentioned that this was a spoiler, they considered it spoiler warning enough. Something along the lines of "speaking of fathers, spoilery information about Darth Vader and Luke Skywalker indicates..."
In short - waaaaaah :( And BEWARE.
In short - waaaaaah :( And BEWARE.