On Wednesday, the “Fall in Line” singer shared a video of Summer joining her onstage as she sang “Beautiful” at the St. Louis concert of her Liberation Tour. Summer cuddled up against Aguilera on a set of steps as the famous mom crooned her hit.
“You wanna hear everybody sing?” she asked Summer. “Let’s hear them sing.” Aguilera, 37, then turned the microphone to the audience members, who belted the next part of the chorus.
“Beautiful. Do you hear that? I love you guys,” Aguilera said before launching back into the end of the song. She added, earning a laugh from the crowd, “Summer, this was way before you were born.”
The singer captioned the video, “Summer begs me to come out every night onstage! And then gets shy … but loves it … she’s taking it all in early … “
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Summer’s 10-year-old brother Max Liron, whom Aguilera shares with ex-husband Jordan Bratman, has also tagged along on his mom’s tour. In October, Aguilera told the crowd at Radio City Music Hall in New York City that Max was backstage.
“My son is backstage tonight. He just flew in,” she said. “The last time I was on tour, I was pregnant with my son. And now he’s back here tonight.”
“My oldest is like, ‘Can I go home and play Fortnite now?’ ” she joked. “I’m like, ‘Ugh … thanks.’ ”
In June, Aguilera told PEOPLE that touring as a mom for the first time would be “scary.” Noting that Max would mostly stay with his dad in Los Angeles to “do his school and be focused,” Aguilera said that Summer, whose dad is Aguilera’s fiancé Matt Rutler, would be traveling with her.
“She’s a mama’s girl and I’ll definitely be taking her on the road with me,” the pop star explained. “She’s going to learn to see life through a different set of eyes.”
“I’m going to try to make it as cushy and comfortable for her as possible because if she’s not comfortable, I’m not,” Aguilera added.