Dr. Weaver is portrayed by Laura Innes, who was promoted to the role of series regular beginning with the third-season episode "Dr. Carter, I Presume", which aired on September 26, 1996.

Her administrative position often forces her to make unpleasant decisions that draw hostility from her fellow physicians, as when she fires Jeanie Boulet in Season 4.

[1] During Innes' first five seasons on the show, little was revealed about the details of Weaver's background which would later become some of her defining traits: her sexual orientation, political beliefs, and even the precise nature of her disability.

In addition, her strong belief in administrative policies would be dragged out into every unnecessary aspect in the workplace (in one episode, Jerry, the desk clerk, brought cake celebrating her day off).

In Season 3, Kerry became an ER attending physician alongside Mark Greene, whom she would always manage to compete with or maneuver to catch the eye of her superiors.

In an early glimpse into her soul, Weaver defended Jeanie Boulet, played by Gloria Reuben, a physician assistant who contracted HIV from her adulterous husband.

Weaver demonstrated a great deal of compassion and a moral commitment to civil rights, and that helped her and Dr. Greene draft an ER policy for HIV-positive employees.

In future episodes, she agreed to look the other way when Dr. John Carter helped a teenage runaway escape her homophobic parents who sent her away to an ex-gay camp.

After Carter was fired from his RA position and had nowhere to live, he followed an ad which led him to Dr. Weaver's house; she had been renting out her basement apartment to college students.

In 1998, during Season 4, Kerry was briefly debilitated when an explosion at chemical plant sent victims flooding in, creating a toxic benzene spill in the ER.

Yet, after an incident involving the hiring of a doctor who turned out to be a very accomplished if bizarre non-physician, Kerry's chances were luckily left open.

At the start of Season 6, word spread that Romano might be up to the position as Chief of Staff, an event that both Kerry and Mark Greene resented and tried to prevent.

She initially refused to accept Dr. Mark Greene's assertion that Lawrence was suffering from the early stages of Alzheimer's disease, but she ultimately faced facts and said goodbye to her role model.

The first coworker Weaver came out to was Dr. Robert Romano, who planned to fire Legaspi over trumped up allegations that she sexually harassed a female patient.

She was therefore unable to provide emotional support to Legaspi, who kept her job, but at the cost of seeing the entrenched homophobia of the hospital administration and her own girlfriend, who remained in the closet.

Kerry also ran afoul of Elizabeth Corday in Season 7 when she had Mark Greene evaluated for professional competency after he showed noticeable personality changes after returning from brain tumor surgery.

Weaver did, however, begin a new relationship with firefighter Lt. Sandy Lopez (played by Lisa Vidal) whom she met in a rainstorm while trying to rescue a pregnant woman from a crashed ambulance.

What followed was a groundbreaking story for American network television as the development of the romance between the two women was treated with the courtship, passion and arguments often reserved for heterosexual couples.

Weaver was finally hauled in by Dr. Carter when he ran from the ER to get her personally from Doc Magoo's, sustaining a painful fall in the process.

The couple did not get much screen time that season, and Weaver was given another story thread about the consequences she faced when she failed to report a local politician who tested positive for syphilis; Alderman Johnathan Bright provided funding for County and a plum position for Kerry, but forced her to do an off-the-record treatment of his closeted gay lover that ended with the lover's accidental death from an allergic reaction to penicillin.

In the 2005 episode titled "Just As I Am," Weaver finally met her biological mother, Helen Kingsley, who turned out to be a conservative Christian, originally from Myrtle Beach, South Carolina and currently living in Terre Haute, Indiana.

Kerry asked Abby (who was expecting a child with Luka) to be Henry's legal guardian in the event that something happened to her, but her surgery was entirely successful.

(Reportedly, this storyline was done, at least in part, because Laura Innes really was starting to develop hip and back problems after ten years of walking with a fake limp for the sake of her role.)

"[3] At the end of the season, Kerry faced criticism for hiring Dr. Victor Clemente (John Leguizamo) as an attending physician, who compromised patient care leading to possible liability and lawsuits to the hospital.

Though she clearly struggled to adjust to her new position, especially with the current ER chief Luka Kovač now being her boss, Kerry was pleased to practice medicine full-time again; she also developed a more friendly relationship with Greg Pratt.

Working back in the ER, Weaver caught the eye of a TV producer filming a news segment with Dr. Morris and literally steals the show.

Kerry decided to leave County General when ER chief Luka Kovač had to enact budget cuts and eliminate an attending position.

As Kerry packed up and walked out of County General's doors for the last time, she only asked Luka to take care of the place for her and advised him not to make her mistake of getting involved in hospital politics, indicating that she forgave him.

[4] Weaver appeared in a flashback sequence in the Season 15 episode titled "Heal Thyself", which was set back in 2002, just months before Greene's death.

During Season 15 episode 19, former co-worker Dr. Doug Ross asked both Sam Taggart and Neela Rasgotra about Weaver (as he found out that they were from County), curious if she was still working there.