Thalia Grace wasn’t supposed to exist. After World War II, Zeus, Poseidon and Hades made a pact not to have any more demigod children. The only brother not to break the vow was Hades, as his two children with Maria Di Angelo who were Bianca and Nico, were born before the war. So the god of the sea had Percy Jackson with Sally Jackson, while the king of the gods had Thalia with Beryl Grace. In his Roman form, Jupiter, he had Jason Grace, also with Beryl.
When she was young, Thalia saw her brother given away by her fame-hungry, attention-seeking mother. Little did she realise at the time that Jason had been given to the wolf goddess, Lupa, to be raised.
Living with her mother was a total nightmare for Thalia. Her mother became so obsessed with getting Zeus’ attention back that Thalia ran away from home once she turned twelve. She met up with Annabeth Chase was seven, and Luke Castellan, who was fourteen, who had all run from poor home lives.
Their protector, the satyr Grover Underwood, failed to get all three demigods to Camp Half-Blood. As a result, Thalia “died” protecting her friends. Furthermore, feeling sympathy for his dying daughter, Zeus turned her into a pine tree that sat at the top of Half-Blood Hill for five years.
Luke’s Betrayal And The Tree’s Poisoning Brings Thalia To The Forefront
Upon Luke’s betrayal and the tree being poisoned, the barrier around Camp Half-Blood started to fade. Percy and Annabeth, along with Percy’s half-brother, Tyson, mount a rescue to save Grover and find the Golden Fleece.
When they place the fleece on the dying tree, Thalia suddenly appears alive at the tree’s base early one morning.
After this, Percy and Thalia are forced to realise that once one of them turns 16, they will be the ones who decide the fate of Mount Olympus. After the deaths of Bianca Di Angelo Zoë Nightshade, Thalia chooses to join her half-sister, the goddess Artemis, and become her new lieutenant, putting her out of running, leaving only Percy to make the decision.
