Embark on a heartwarming journey of family, friendship, and the joy of becoming a big sister in "The Little Agent and The Letter Twins," a touching children's book by Alayah Jenkins. Agent Three is back, and this time, she's about to experience the most incredible adventure of all-becoming a big sister to the adorable Letter Twins, or so she thought. As excitement and anticipation fill her heart, Agent Three also feels a hint of nervousness about what this new role will bring.