|Relationships:||The Cahill Family|
|First Appears In:||The Black Book of Buried Secrets|
|Last Appears In:||Vespers Rising|
HistoryKatherine was one of the five original Cahill siblings in the Gideon family. She was the second oldest of her siblings, as she was born in 1492 somewhere in Ireland. Like her father, Gideon, Katherine was fascinated by science and technology. When she was little, Thomas and she spent endless hours dreaming of going on great adventures. But that all changed in 1507. Both she and her brother, Thomas, believed Luke was responsible for the fire that killed their father, so they traveled to Portugal together to protect their Clues from their brother. In Portugal, they met Louisa, Thomas' first love, and Thomas begged Katherine to stay there for a little longer, so they stayed for three years. An angry Katherine, believing that Thomas chose love over duty, ran away from her brother in the middle of the night with his Clue and escaped to Egypt. Ever since then, Thomas and his descendants have hated her and her descendants. She then became one of the world's first Egyptologists, learning how to read and write Hieroglyphics even before the Rosetta Stone was found. There she hid a Clue for her descendants to find. According to the back of her card, she wrote that Luke was "sneakier than a serpent, and even more deadly" and Jane was "too young, too fanciful to make it on her own" and Thomas "ignored his duty, my greatest disappointment" and her Father "valued his secrets more than his family" which means he didn't care for his family, and her mother, Olivia, was "blinded by love and crippled by loyalty". Katherine died at a unknown point of her life in the Tutankhamun Statue in Egypt while hiding a Clue.
"Ingenuity above all"
- Gideon Cahill - Father (deceased)
- Olivia Cahill - Mother (deceased)
- Luke Cahill - Brother (deceased)
- Thomas Cahill - Brother (deceased)
- Jane Cahill - Sister (deceased)
- Madeleine Cahill - Sister (deceased)
- Madeleine the Matriarch - grandmother (deceased)
- Toyotomi Hideyoshi - Nephew (deceased)
- Louisa - Sister-in-law (deceased)
- William Shakespeare - Great Nephew (deceased)
- Winthrop Cahill - Nephew (deceased)
- Many other relatives and descendants
PersonalityAs founder of the Ekaterina Branch, Katherine must have loved technology and the sciences. Bae Oh even said that she was the "queen of ingenuity". She was also courageous since it was brave for a woman to travel alone in her time, and she did so. She seemed to care about her descendants, leaving them a Clue in the Sakhet statues, and in her diary. Katherine was also extremely clever, cracking the code of Hieroglyphs, 200 years before the Rosetta Stone was found.
When Dan Cahill found her portrait, she is described as a young woman with short blonde hair and intelligent eyes, wearing a brown dress. Unlike most girls at the time, she wore breeches rather than dresses. Regardless of that information, she is shown wearing a dress on both of her cards. In Vespers Rising, when she was still fifteen, Gideon described her with short dark hair, and wore a frock and breeches like a boy with dark eyes.
A portrait of Katherine Cahill was found along with the pictures of her siblings in Paris.
It is revealed that Katherine went to Egypt to hide one of her Clues, Myrrh. She bought three Sakhet statues, modified them to hold secrets to the Clue and hired tombrobbers to hide them in tombs of queens.
Her tombstone was on Cahill Island.
In Vespers Rising, Katherine was seen by Gideon taking apart an ancient family heirloom, a globe, but he didn't punish her, as he was surprised she didn't have it taken apart years ago. In the prequel it's obvious to see how Thomas looks after her, Luke taunts her, and Katherine and Jane seem to have very little contact at all.
This may have been the Armillary Sphere.
Katherine was skilled in technology and mechanics, which is passed on the Ekats, who are good in math, science, etc.
- On Katherine's notebook, there is the alchemical symbol for Phosphorus, which is one of her Clues.
- Katherine was as smart as her father, being the only one in her family besides her father to outsmart Damien Vesper.
- She is holding an Armillary Sphere, according to Card 99 which may be due to her interest in astronomy.
- Her name mean Ekaterina in latin which is probably why she named her branch Ekaterina.