Alex Claremont-Diaz is a fictional character from the novel "Red, White & Royal Blue" by Casey McQuiston. He is the son of the first female President of the United States and serves as the First Son. Alex is known for his charismatic personality, intelligence, and strong sense of justice. Throughout the story, Alex navigates his complex relationship with Prince Henry, a member of the British royal family. Their evolving friendship and romance challenge societal expectations and highlight themes of love, identity, and political duty. Alex's character embodies resilience and the pursuit of happiness in the face of public scrutiny.