"We absolutely wanted to keep this private, but we did not want him to get away with it. He sexually assaulted her," Andrea said in court

Taylor Swift‘s mom Andrea became emotional on the witness stand Wednesday afternoon as she recounted the moment she learned of her daughter’s alleged assault in 2013.

Andrea — who is a familiar face at Swift’s sold-out concerts — said in court she first learned of Mueller’s alleged groping after her daughter’s concert on June 2, 2013. “Mom, a guy just grabbed my ass,” Andrea recalls Swift telling her in the dressing room after her show.

After Andrea saw the photo that was taken of Mueller, his girlfriend and Swift at the meet-and-greet, “I knew there was something horribly wrong in that picture,” she testified. “I know those eyes better than anybody. She was pulling away. She has that smile frozen on her face, but there’s something going on in her eyes. I just looked at it and I was sickened.”

Swift, 27, was “really shaken, she was humiliated, she was horribly embarrassed because he grabbed her bare ass,” Andrea testified.

Court sketches of Taylor Swift and David Mueller in court in Denver, Colorado.
Credit: Splash News

During cross-examination by Mueller’s attorney, Gabe McFarland, Andrea said she was “upset to the point of feeling like I wanted to vomit and cry at the same time” after learning of the alleged incident.

She and the rest of Swift’s management team decided to inform KYGO of the alleged assault because “we all felt as a group that this was a responsibility,” she said.

Andrea described in court how she had been accompanying Swift to radio stations across the United States since she was 15 years old. Though many producers saw Swift as a “daughter or sister,” Andrea or a family member always accompanied her.

“What could happen to a young woman if she didn’t have a companion to accompany her?” she said on the stand.

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Swift’s mother also reiterated they did not involve police after the alleged incident because they “did not want this event to define her life.”

“I did not want every interview from now on to have to make her include what happened to her. I did not want her to have to live through the endless memes and GIFs that tabloid media and internet trolls would come up with,” she added. “We absolutely wanted to keep this private, but we did not want him to get away with it. He sexually assaulted her.”

During questioning by Swift’s attorney, Doug Baldridge, Andrea recalled raising Swift on their Pennsylvania Christmas tree farm. Learning to play the guitar at 11 years old, Swift would play for eight hours a day and had “much more interest in performing than horseback riding,” said Andrea.

Taylor Swift,David Mueller
Credit: Jeff Kandyba/AP

While Andrea spoke clearly and with conviction while taking the stand, she did become emotional and dabbed at her eyes when discussing how the alleged assault impacted Swift.

“She couldn’t believe that after the incident, she thanked him for being there. She said ‘Thank you.’ It was destroying her. It made me question why, as a parent, I had encouraged her to be so polite,” she said, tearing up.

Andrea also claimed Swift’s team approaches meet-and-greets differently now. “It’s absolutely shattered our trust. Our meet-and-greets are much smaller. We have metal detectors. We do background checks. It scared us really badly.”

Taylor Swift,David Mueller
Credit: Jeff Kandyba/AP

Mueller first sued Swift in 2015, claiming he lost his job after the singer’s security team accused him of groping her butt during a meet-and-greet at the Pepsi Center in June of 2013.

Mueller denied the allegations and also accused his colleague of sexually assaulting the singer, but a rep for Swift told PEOPLE at the time that “the radio station was given evidence immediately after the incident” and “made their independent decision.”

One month later, the “Out of the Woods” singer countersued Mueller, saying in court papers he “intentionally reached under her skirt, and groped with his hand an intimate part of her body in an inappropriate manner, against her will, and without her permission.”

Swift — who has been largely out of the spotlight in 2017 — is expected to take the stand at some point throughout the nine-day trial.