Little is known about Katie's personal life, other than she had a relative named Amy. As an adult, she joined the BAU and is on a familiar basis with the team. She then transferred to the Crimes Against Children Unit, which she now heads.
When Agent Amanda Gilory sees an online photo of a boy who has been abducted years ago, she calls in Katie, who identifies the boy as "Peter", a young boy that had been abducted by a pedophile who they have been tracking through an online chat of pedophiles. She calls the BAU for help. When she arrives to their headquarters, she is greeted by Gideon and Hotch; Katie informs the team about the case and assists them with everything they need regarding information. She accompanies Hotch, Gideon, and Morgan on the plane while Elle and Reid go to the CAC headquarters, and Garcia and JJ monitor the online chats at the FBI Headquarters. When Katie's team arrive, they manage to track a boy named Kevin Rose posting online pornography of himself. Through him, they track another pedophile named Hayden Rawlings, who is arrested. By the end of the episode, "Peter"'s real abductor is found and arrested, while Katie herself rescues the boy.
- Katie's character was based on Emily Vacher, an agent currently assigned to the FBI's Albany Division, Syracuse Resident Agency. Vacher was once a member of the Innocent Images National Response Team (the real-life organization the Crimes Against Children Unit is based on) and also managed the FBI's Endangered Child Alert Program.
- Katie has aviatophobia, the fear of flying.
- She prefers to be called Katie instead of Agent Cole.
- She was one of the first profilers and clinical psychologists in the BAU.