So I think everyone here knows who Don Carlos is, but for those of you who don't, he was the "crazy" Heir of Philip II. However some of you might not know that he went "crazy" after suffering severe head injuries from a fall down the stairs in 1562. I might he wrong here but I can't find any sources suggesting his mental illness had started before his fall down the stairs. So what if he didn't fall down those stairs? How would a sane Don Carlos' life look like? Would he be allowed to take command in the Netherlands? Or would he be sent to Italy? And how would his eventual reign as Carlos II look? Oh and one more thing. Looking at the genealogical charts, Carlos seems to have been the Heir presumptive to his first cousin Sebastian of Portugal. So would he reign in Portugal first or would Philip II usurp his rights there?