A Kentucky mother says she is “devastated” after a local Christian school expelled her 15-year-old daughter over a photo showing her wearing a rainbow sweater in front of a similarly decorated cake.

Kayla Kenney, who was a freshman at Whitefield Academy in Louisville, Kentucky, wore the rainbow shirt to a Texas Roadhouse restaurant for her Dec. 30 birthday celebration. Her mother, Kimberly Alford, shared a photo of the teen about to blow out the candles on a birthday cake topped with rainbow icing on her Facebook page, prompting an email from Bruce Jacobson, Whitefield’s head of school, last week.

The photo demonstrated “a posture of morality and cultural acceptance contrary to that of Whitefield Academy’s beliefs,” Jacobson reportedly wrote. Noting that the image followed two years of “lifestyle violations,” he then formally terminated Kenney’s enrollment.

Alford told ABC News in a Tuesday interview that the school, which serves students in preschool through 12th grade and is affiliated with the Highview Baptist Church, rejected her efforts to file an appeal. When she contacted Jacobson by phone, she said he agreed to change the expulsion to a voluntary withdrawal so that it doesn’t appear on Kenney’s academic record. However, he said the rainbow’s symbolic connection to the LGBTQ community was a factor in her daughter’s dismissal.

Noting that Kenney does not identify as LGBTQ, Alford said her daughter’s shirt and cake were meant only to appear festive.

“I feel judged [and] she feels judged,” she said. “There was nothing intended by that and even when I went back and got the receipt from the bakery, it didn’t say anything about representation, it just said assorted colors.”

In a separate interview with The Washington Post, she added, “Rainbows don’t mean you’re a certain gender or certain sex or sexuality.”

According to its code of conduct, Whitefield Academy “unapologetically advocates preservation of a uniquely Christian worldview.”

“If the home environment is not in harmony with the school’s doctrinal belief in the centrality of Jesus Christ and the authority of Scripture and Biblical lifestyle, it will be difficult for the school to cooperate with the home and achieve the goal of a student becoming Christ-like,” the parent/student handbook reads. “In such cases, the school reserves the right, within its sole discretion, to refuse admission of an applicant or to discontinue enrollment of a student.”

LGBTQ advocacy groups have blasted the decision.

This expulsion from Whitefield Academy is sad and outrageous. https://t.co/7usylQcB03 — Fairness Campaign (@FairnessCamp) January 14, 2020

“The rainbow is a symbol that God uses as a promise to us. It is God’s promise never to destroy us,” Ross Murray, who is the senior director of GLAAD’s Media Institute, wrote on Twitter. “This school clearly doesn’t see God’s promise for all of humanity, and they are threatened by a symbol that has meaning for the LGBTQ community.”

In an email to HuffPost, Whitefield Academy said Kenney’s expulsion came after “numerous” violations of the school’s code of conduct. Reports suggesting the decision was based solely on the social media post, they added, were “inaccurate.”

“All parents who enroll their children in our private school know up front that we ask the students to adhere to a lifestyle informed by our Christian beliefs,” the school wrote. “There are numerous school options in our community for students who do not wish to attend a Christian-based school, and we wish our former student all the best as she finds a learning environment that is right for her.”

Kenney has since enrolled in a public school. By speaking out, Alford said she simply wants to draw attention to the case so that it doesn’t happen again to a different student.

“You know we teach our kids what would Jesus do,” she said. “What would he do here?”