I heard they become much much calmer after 2 years of age. I already notice a huge improvement in Drogo as each week passes. When he was 2 months of age, he was like a little fluffy tasmanian devil
but now, after only 3 months, he is a heck lot calmer, doesn't bite only when he really wants to play and he is actually very moderate energy-wise. To my surprise, a lot of dog-owners noticed how well-balanced he is for his age. Also, they were fascinated by the fact that he doesn't leave our side when he is off-leash.