Amy Cahill is the 18th card of the 39 Clues cards.
"Fourteen-year-old Amy Cahill likes history, books, Egyptian Mau cats, and memories of her mother. She does not like breaking into hotels, high-speed canal chases, or being mobbed by angry monks. Amy thinks she has no chance of finding the 39 Clues before her power-hungry relatives, but that's where she might be wrong. Because Amy has more Clue-hunting skills than she believes. . ."
Top Secret Edit
The top secret from this card is a message from William McIntyre to Grace Cahill about a test that he gave Amy at a museum while she was on a field trip to find her strengths and weaknessses. He says that they might want to start evaluating Dan too. This message can also be seen in the Agent Handbook.
This card, when combined with Card 17, Card 19, Card 20, Card 21 and Card 22, forms the Clue Tungsten.
This card tells you that Amy once believed in Santa Claus.