Beyoncé and Solange Sang Mom Tina a Song Before Cancer Surgery (Exclusive)

Tina Knowles shared a special moment with her daughters, Beyoncé and Solange Knowles, before she underwent surgery late last year following a stage 1 breast cancer diagnosis.

While speaking exclusively to PEOPLE at the 27th Annual Angel Ball held at Cipriani Wall Street in New York City on Monday, Oct. 27, Knowles, 71, spoke about her cancer journey, which she previously opened up about to PEOPLE, as well as in her recent memoir, Matriarch.

In the book, which was released in April, Knowles explained how her family had been supportive after doctors discovered the cancer in her left breast last July.

Discussing the diagnosis with PEOPLE at Monday’s event — which raises funds for cancer research — she says her daughters Beyoncé, 44, and Solange, 39, even gave her a bit of a performance before she was taken into surgery. 

“Right before I was wheeled in to get the surgery, my girls sang a gospel song, ‘Walk With Me,’ which I absolutely love,” Knowles, who was a guest of honor at the black-tie ball, tells PEOPLE.

Knowles also says her girls had her “laughing” at the time after telling her about the demure trend, which was created last summer by TikTok creator Jools Lebron after she posted a video showing how she got ready for work in a “demure” way.

“There was this woman who was saying, ‘You have to be demure,’ and they just kept saying this and showing me that video,” Knowles adds. “I went in there laughing and feeling so blessed — like everything was going to be okay. And it was. It so warms my heart.”

Knowles was supported at Monday’s event by her granddaughter Blue Ivy Carter, 13 — who is the daughter of Beyoncé and Jay-Z — with the teen looking pretty in pink, wearing a silk gown teamed with a corset bodice for the bash.

Knowles previously opened up about her private breast cancer journey while speaking to PEOPLE in April’s World’s Most Beautiful issue.

“It’s important not to slack on your mammograms,” the superstar mom and author said at the time.

She said she “struggled” with whether or not she wanted to share her cancer journey in her memoir, “because I’m very private.” 

“But I decided to share it because I think it’s a lot of lessons in it for other women,” Knowles added. “And I think as women, sometimes we get so busy and we get so wrapped up and running around, but you must go get your test. Because if I had not gotten my test early, I mean, I shudder to think what could have happened to me.”

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In fact, Knowles herself had missed getting her scheduled mammogram. “I forgot that I didn’t go to get my test two years before I thought I had,” she shared, “because Covid came and they called me and canceled me and they said, ‘we’ll call you when we start testing again.’ And I just thought I had done it. So you cannot play around with that.”

Knowles explained how her daughters grappled with the news about her diagnosis in Matriarch, writing that Beyoncé “took it well, staying positive, and I could already feel her mind racing, focusing on this as a task to tackle with precision.” 

Meanwhile, Solange said, “Mom, we are going to take care of this.” With bonus daughters Kelly Rowland and her niece Angie Beyince also by her side, she wrote, “My girls became my team.”