Who was the small boy seized by the creature?

The small boy seized by the creature is William, the youngest son of the protagonist, who is taken by the monster in a pivotal moment of the story. This event serves as a catalyst for the protagonist's subsequent actions and reveals the creature's violent nature. William's abduction highlights themes of innocence and the impact of fear on the characters' lives. His fate drives the narrative forward, prompting a desperate search for answers and justice.