The Brothers Garcia: Mysteries of the Maya(2003)

In this movie detour from the Brothers Garcia TV series, the Garcia family takes a trip to Mexico's Yucatan Peninsula to learn more about their heritage. There, the kids get mixed up in a magical adventure that takes them directly to the historical roots of the Mayan culture when they encounter a living ancestor of theirs who must be reunited with his lady-love or else he'll be cursed to live as a shadow serpent forever.