I bought all Nightingale cds today

Maybe someone can help me here.. A couple of years ago I downloaded an mp3 titled "Son of I". I have yet to buy the album "I" but again got some mp3's of it and I noticed the song Drowning in Sadness has almost identical vocal patterns and lyrics as well as the music to the aforementioned "Son of I". Only difference with Drowning in Sadness is the introduced gothic style voice, keyboard parts and some guitar work. Now my question is, where the hell does "Son of I" come from? It almost sounds more Edge of Sanityish or something but I'm not for sure because I haven't heard it in a long time. Or did the guy who encoded the mp3 just totally get the title wrong and it's actually just another track off of "I"?


So many cd's to get....