Cousins Ava and Nadeem are fifth graders and best friends. Ava is Jewish, from Sephardic descent, and Nadeem is Muslim; this opens them up to comments from bullies at school. After a particularly tough day, the two confide in their Granny Buena, who tells them a story of a legendary ancestor, Ester ibn Evram, and her role in saving a famous Muslim prince, Abdur Rahman, in Medieval Spain. As they look through Nanny Buena’s button box, which holds one of Ester’s buttons, the two discover that have traveled through time and landed back in Medieval Spain, just in time to witness – and maybe assist! – Ester ibn Avram on her quest, and help create a “legendary Golden Age for Muslims, Jews and Christians”. The story is exciting and the relationship between Ava and Nadeem is wonderfully supportive. Granny Buena speaks with a sprinkling of the Judeo-Spanish language Ladino, which leans closely to Spanish, giving readers some exposure to a new language. Back matter includes a glossary and an author’s note about Sephardic Jews, Muslims, and the actual Prince Adur-Rahman (Ester ibn Avram is fictional). An excellent choice for readers who enjoy the Magic Tree House series, and very similar to Marcia Berneger’s A Dreidel in Time (2021).