Meh, I don't really think so at this point. Firstly, that specific event isn't a very big part of the story (other than the after effects, which I've not mentioned at all), so it isn't really a "huge" spoiler. Secondly, that happened quite awhile ago, so it's out of the bounds of a reasonable time limit for spoilers. It's like if you haven't seen or read Harry Potter stuff yet. At this point, sorry but I shouldn't need to put spoilers in a public forum when saying Harry was unwittingly a horcrux for Voldemort. That said, I've decided to add spoiler tags anyway, both there and here.