Katherine Sullivan is one of the main protagonists in the TV series, The Sullivans.
Born in New York City, New York in March 1990, Katherine was the third oldest of the four children of NYPD detective Gordon Ashford and Elizabeth Ashford. When Katherine was 10, Gordon was about to present damning testimony against a notorious New York mob boss after witnessing the boss and one of Gordon's police colleagues who had turned corrupt murder an informant and record video of the killing. After he hid the video, Gordon and his family, including Katherine, were about to put in witness protection when a mob hitman known as "The White Tiger" murdered her parents, her two older siblings Doug and Barbara, and several of her father's police colleagues. She and her younger Joey managed to escape to the subway and hide from the danger. After the tragedy, she and Joey were raised by their paternal uncle Henry, a sheriff of a New York county, and his relatives. In adulthood, Katherine and Joey became estranged when the former wanted to find and catch the hitman responsible and the latter wanted to forget the tragedy and move on.
After getting a law degree in Yale, Katherine moved to Denver for a fresh start. She joined the Denver D.A. office and soon became an ADA. One night, she met Drake Sullivan at the bar and they flirted with each other, despite their differing personalities. Then Drake's ex-girlfriend Sharon Carlyle showed up and after some time talking with both of them, Drake opted to drive Sharon home. Katherine herself left a while afterward. Shortly afterwards, Drake was accused of murdering Sharon and Katherine ended up as second chair to the ambitious EADA Milo Stetler on the case. Remembering how Drake was with Sharon and noticing some inconsistencies in Stetler's opening statement, she came to believe that he was innocent. With help from some allies, including then-ADA Andrew Bishop and then-Sergeant Eugene Winder, they discovered that Stetler had deliberately suppressed video evidence that exonerated Drake of the murder, and that the real murderer was another one of Sharon's ex-boyfriends, Henry Addison, the son of then-Senator Louis Addison, who was complicit in covering up his son's crimes with Stetler. After proving his innocence, Drake profoundly thanked her for clearing his name and asked her out on a date, which she accepted.
After three years of dating, Katherine and Drake were happily married. Afterwards, she gave birth to their son Finn and daughter Mary. As her conviction record was high, Katherine became Executive Assistant District Attorney.
A tough, hard-nosed Executive A.D.A. After she and her younger brother Joey witnessed the murders of their parents and two older siblings by a mob hitman, she became dedicated to protect families from suffering the same fate she endured in adulthood. She is a very intelligent woman and is known to be feisty and stubborn at times, like her husband Drake. As a prosecutor, Katherine is stern and uncompromising against those who commit unthinkable crimes against families, women and children, but she is very compassionate towards victims of domestic violence, child abuse and rape. She is a good wife to Drake and loving and sometimes overly protective mother to their children, Finn and Mary.
- Drake Sullivan (husband)
- Finn Sullivan (son)
- Mary Sullivan (daughter)
- Gordon Ashford (father, deceased)
- Elizabeth Ashford (mother, deceased)
- Doug Ashford (older brother, deceased)
- Barbara Ashford (older sister, deceased)
- Joey Ashford (younger brother)
- Henry Ashford (uncle)
- Ryan Sullivan (father-in-law)
- Rachel Sullivan (mother-in-law, deceased)
- Amanda Whitman (sister-in-law, deceased)
- Wesley Whitman (nephew)
- Lucas Whitman (nephew)
- Lydia Graves (sister-in-law)
- Christine Graves (niece)
- Matthius Graves (nephew)
- Jeffery Graves (nephew)
- Robin Graves (niece)