Complex sentence: Constantine was born at Psychiko Palace in Psychiko, a suburb in northern Athens, the nephew of King George II and the second child and only son of the king's brother and heir-presumptive, Crown Prince Paul.
Split into simpler sentences: Constantine was born at the Psychiko Palace in Psychiko, a suburb of Athens. He was the nephew of King George II, and also the second child and only son of the king's brother and presumptive, Crown Prince Paul.