|“||I have fed her, clothed her, loved her going on nine years. You think motherhood's just about blood? You don't know the first thing about it.||”|
At some point a long time ago, Celia had a daughter named Alex who died of unknown causes. To replace Alex and fill the hole in her life, in 2006, Celia kidnapped a young girl named Annie Jones and made her a member of her "family," renaming her Alex and using her as a lure for prey for her and her "family." However, she didn't turn Annie into a vampire so she could watch her grow up.
In 2013, Alex brought home Richard Beesome for Celia and her "family" to feed on. The family, ravenous, descended upon Richard and drank him alive. However, for some reason, Celia and the other vampires turned Richard into a vampire rather than killing him. This led to Richard going home and killing his family after he lost control over his bloodlust.
In 2014, while Celia's "family" was out on a hunt, Alex ran away out of guilt over her actions.
After learning that Alex has run away, Celia and her "family" work to track her down, hunting down the two bus station workers who helped her flee town. Celia is angry when one insults her "family" and after getting what they need from her, has her "sons" kill the woman. Celia, Connor and her other son leave for Sioux Falls, South Dakota where Annie fled to, leaving Dale to dispose of the bodies in a woodchipper near their nest.
In Sioux Falls, Celia and her "family" travel to the police station where they beat the location of the cabin Alex was taken out of Deputy Frank, but leave him alive. At the cabin, Celia stays in the truck while her "sons" kidnap Annie and knock out Sheriff Jody Mills who was looking after her.
Returning to the nest, the vampires find Dale dead due to Sam and Dean and Celia forgives Alex and asks her to become a vampire. Alex agrees and Celia turns her. Shortly afterwards, Sam, Dean, and Jody raid the nest and Jody finds Alex. While Jody is distracted with Alex's new state, Celia knocks her out from behind. Celia tries to get Alex to feed off of Jody and finish her transformation into a vampire, but Alex refuses as Jody was so good to her. Jody realizes that Celia is trying to use Alex to fill the hole in her life created by the death of her daughter, similar to how Jody is trying to fill the hole left by the death of her own family at the hands of zombies. Celia admits this but then starts beating on Jody before going to feed on her. Before she can, Alex injects Celia with dead man's blood, incapacitating her. Celia is stunned and angry at Alex's betrayal, but Alex just apologizes. Telling Alex not to watch, Jody decapitates Celia, killing her. At the same time, Sam and Dean kill her two remaining "sons" and eliminate the last of Celia's vampire "family."
Afterwards, as Alex never fed, Sam and Dean are able to use Celia's blood to make the cure and turn Alex back into a human.
Three years after Celia's attack on him left him a vampire and his family dead, Richard Beesome goes after Alex for revenge in her part of Celia's attack. While held prisoner, Alex tells Richard that Celia and her family sometimes fed on her too when the hunting "went dry."