Darius/Draven & Gangplank connection?

With all the fuss about the new champion having to have a relationship to Baron Nashor because they have similar sprites i have to ask if Gangplank is the long lost brother of Darius and Draven. I know the two of them are orphans and GP's dad was a pirate so he probably got around... It could just be the same artist for the splash pictures but Draven and GP look more than a little similar.