The doubt

Here we have Simba and Kopa again!  
Kopa always was stubborn and carefree fellow and never think of himself as a future king, and that`s very troubling Simba. And he reminds his son about his future responsibilities, but Kopa now more annoyed, then 
convinced. He just too young and sure Simba will live a very long time... He wants explore the world, explore the whole life. Royal life is too slow and boring for him right now.