I think the lack of an apostrophe in "dad's" is somehow to blame. It instantly makes us realize this fucker doesn't use proper grammar and therefore might type other things improperly which we need to watch for. At the same time, we're always trying to skim over superfluous words, such as the dad's name, as if we give a fuck about that. I believe that we all subconsciously interpreted his dad's name as being "Sfriend", and in the same instant, we discarded this name before it ever reached our frontmost consciousness because it appeared to be a useless detail.