Nothing is known about Kathy's life prior to or as the outbreak began.
Kathy is first shown when Tara is being held in a cabin, Beatrice questions her with Natania and Kathy. That night, the women have supper and attempt to persuade Tara to stay with them in Oceanside. However, Tara wants to go back home to her girlfriend and the women offer to escort Tara back to the bridge where she last saw Heath.
While in the woods, Tara catches on to the real plan: Kathy and Beatrice are going to kill her and manages to flee from them, but Beatrice finds Tara and the women scuffle. With her rifle aimed at Tara, she is knocked out by Cyndie. A short time later, Beatrice and Kathy arrive at the bridge and bring Cyndie back home after Tara successfully escapes.
Kathy appears when bombs begin to go off in the outskirts of Oceanside, as she is running she is stopped by Daryl, as is told to put her hands behind her head. She obeys him and is brought to the woods with the other Oceanside residents.
When Natania and Cyndie talk about fighting the Saviors, Kathy seems somewhat interested, however it is unknown if she was willing to join the fight. Shortly after, she is among the survivors to help defend the Oceanside residents from walkers.
After the deal is over, Kathy watches as the Alexandrians take their guns.
Kathy is present when Cyndie must decide whether to kill Aaron and Enid or not, and Rachel suggests that they kill them, but Cyndie lets them live, and Kathy, along with the Oceansiders escort Aaron and Enid out, refusing to join the fight against the Saviors, and warns them never to come back.
Kathy is seen with the women of Oceanside returning from fishing, an emaciated and weak Aaron kills a walker that appears nearby before collapsing. Having been spotted in the area often by the women, Aaron is ignored except for Beatrice to tell him to find something to drink.
Later, Kathy and the residents find an exhausted Aaron, begging them to join the fight against the Saviors as they would otherwise continue to be fearful of the outside world.
Just as the Saviors arrived at the Hilltop to slaughter the people inside, Kathy, along with Rachel, Cyndie, and several Oceanside warriors, ambushed the Saviors with Molotov cocktails, effectively wiping them out and saving the town.
Having moved from Oceanside to the work camp along with several other residents, Kathy is part of the team of laborers working to build a bridge connecting the communities' trade routes. One morning, as Rick travels throughout the camp, Kathy and Beatrice receive weapons from Rosita at the camp's armory. Later that day, at the lumber yard, Kathy is among those to arrive in time to save Daryl, Jed, another Savior, and the injured Aaron from a group of zombies that had suddenly ambushed the lumber yard.
As tensions grow at the work camp, members of the Sanctuary get into a fight with the other communities. Kathy gets involved in the scuffle until Laura and Alden break up the fight. She watches on as DJ and Norris threaten the survivors with axes until Rick arrives in time and disperses the crowd. Later, Kathy is present at her former community and watches on as Arat is set to be executed for her heinous involvement in the murder and execution of the people of Oceanside, including Cyndie's family and Beatrice's husband.
Kathy smokes and chats with Beatrice in the camp as Rick speaks with Eugene about the bridge project. Later, she is horseback and aims her gun at the Saviors when they return to the camp armed with guns and weapons. After gunshots go off, she is knocked off her horse as it runs away from the commotion.
Upon returning to the camp, Rick finds several reanimated residents, including a zombified Kathy. Though weak, Rick manages to shoot her in the head and Kathy's body falls on top of him.
- Killed By
- Jed (Alive, Off-Screen)
During the shootout between the rebelling Saviors and members of the Militia, Kathy is shot in the chest by Jed.
- Rick Grimes (Zombified)
With the last of his strength, Rick manages to shoot a zombified Kathy in the head.
This list shows the victims Kathy has killed:
- Norris (Alive, alongside Carol, Jerry, and Beatrice)
- Numerous unnamed Saviors (Alongside her fellow Oceansiders)
- Numerous counts of zombies and unnamed people
- Kathy is the last named person that Rick Grimes kills during his time on the TV Series, living or otherwise.