From a Bathtub Cake to Younes Bendjima: Inside Kourtney Kardashian's 40th birthday bash just as her ex-husband Justin Theroux was making his. He's unexpectedly coming over, and the Treasury are hosting a first birthday bash for him this evening. Check Out Our Favorite Running Gags From the FX Comedy. He is wondering why the big Birthday bash is not held a few weeks later- for HIS birthday!! The Rats: Rats, rats, we are the absolute best party ever!