"Horrid Henry's Christmas" is a children's book by Francesca Simon featuring the mischievous character Horrid Henry. In this story, Henry is excited about the holiday season but finds himself in various humorous situations as he tries to navigate Christmas preparations and family traditions. Throughout the book, Henry's antics lead to chaos, including his interactions with his brother Perfect Peter and their parents. The story captures the fun and challenges of Christmas from a child's perspective, making it relatable and entertaining for young readers.