Apollo is a Greek God and the son of Zeus and the Titaness Leto. He is the younger twin brother of the goddess Artemis. He eventually married the mortal hero, Hyacinthus, whom he granted immortality to become his immortal husband. He is the God of Archery, Music, Poetry, Light, the Sun, Art, Oracles, Prophecy, Disease, Reason, Truth, and Knowledge. He and Artemis are jointly known as the Twin Archers. As the God of Truth, Apollo is incapable of lying. Everything he says is true.
Apollo inherited his power over the sun from the original Sun God, Helios, when the Romans downsized the Olympian Pantheon. As such, he drives the Sun Chariot across the sky every day, though he often tasks his attendants--the Nine Muses or his Four Celadons--with driving it in his stead.
As Athena is regarded as Zeus' favorite daughter, Apollo is his favorite son. However, few realize this as Zeus often grows weary with his son's more outlandish behavior. With the mortal Naomi Solace, Apollo is the father of Will Solace. Also, with the mortal Emily Zhang, he is the father of Frank Zhang. With the mortal Augusta McKinley, he is the father of demigod Octavian McKinley, though he did not bless the child with any special powers due to his blood-thirsty nature.
Of all the Olympians, Apollo has the closest relationship to Hades. This stems from his deep love for Hades' son Hyacinthus. As such, the two regularly visit the Underworld to have dinners with both the Lord of the Dead and Queen Persephone. Apollo's aunt, Hestia, often comes to these dinners to see her younger brother.