what is the connection of the game between Assassin's Creed and Watch Dogs?

Ok, guys. After i searched about Assassin's Creed vs Watch Dogs and i found about Assassin's Creed and Watch Dogs Connection. What is the connection about these two games?

Only if you go into the bunker if you hack one of the dedsec log things you will get a video of a father watching his son play a video game with this conversation " so why is he talking to a guy he killed?" "It's a confession" "why is he doing a confession to a guy he killed?" " because dad he is an assassin."