title: List of The 39 Clues characters
context: Amy and Dan Cahill (both from Boston,who are kids that took up the quest). Nellie Gomez (Also from Massachusetts) serves as their au pair and supervisor.[29] They are the protagonists of the franchise. Amy is fourteen years old while Dan is eleven. Both of them have jade eyes.[30] Amy is shown to be intelligent and analytical, while Dan is more active, with a photographic memory. Amy, however, is agoraphobic and pyrophobic,;[2][31] while Dan has asthma and is claustrophobic. They were both wards of Beatrice Cahill since the death of their parents Hope Cahill and Arthur Trent.[32] Throughout the hunt, Amy, and Dan provided the least power to search for the Clues. Surprisingly, they have collected as many Clues as everyone in the hunt, with the help of Nellie Gomez . In the end, Amy and Dan reunite the Cahill family altogether, bringing peace to every Cahill who worked almost 500 years for finding the 39 Clues. Following the events of Into The Gauntlet, and after making peace with Ian and Natalie Kabra, Hamilton Holt, Alistair Oh, Sinead Starling and Jonah Wizard, Amy is named their grandmother Grace's successor and head of the family.[5] They are now in custody of Nellie Gomez and Fiske Cahill. Their branch is revealed late in the series to be Madrigals; the secret fifth branch descended from Madeleine Cahill.[5] Amy's official card is No. 18 while Dan's is No. 2.[9]
question: Who is the protagonist of The 39 Clues?
answers: Dan Cahill