Lopez, 51, performed at Global Citizen's"Vax Live: The Concert to Reunite the World," and invited her mother, Guadalupe Rodríguez, up for a cover of Neil Diamond's 1969 hit, "Sweet Caroline." It's the "lullaby" Rodríguez used to sing Lopez when she was a kid.
"Mom, is it true you used to sing me this song when I was a baby?" Lopez asked Rodríguez, 75, onstage.
"When I used to rock you... I would sing, 'Sweet Jennifer,'" Rodríguez confirmed.
"Sing it to me just like you used to sing it to me," Lopez said, enlisting the audience's help. The crowd, which consisted of 20,000 fully vaccinated frontline heroes, joined in and belted out the "Sweet Jennifer" rendition.
After the "Sweet Jennifer" moment, the crowd at SoFi Stadium in Los Angeles's Inglewood neighborhood stayed on their feet to hear Lopez finish singing the classic version. It was a touching moment as Lopez told the crowd she, like so many people, was unable to see her mom last year amid the coronavirus pandemic.
The concert, which airs on various networks Saturday, May 8, aims to raise COVID-19 vaccine awareness while calling on world leaders to help make vaccines more accessible in the poorest parts of the world.
When Lopez returned later during the pre-taped show, it was a bit of a different vibe.
The triple threat threw on a neon bodysuit and black leather knee-high boots for a sexy performance of "Ain't Your Mama" — although the Hustlers actress had to wait a while before she could get going.
Host Selena Gomez and Chrissy Teigen, who introduced Lopez's second performance, had some teleprompter hiccups. The stars ended up doing multiple takes while Lopez stood onstage with her dancers, arms up and ready to go. But everyone — J.Lo included — laughed through it.
When Teigen messed up her lines before throwing to Lopez she quipped on the microphone, "I f***** up too, Selena!" causing the audience to erupt. The Cravings author joked about the mishap later on Instagram, writing "it was truly an honor" to flub her words in public again.
"I missed that. I miss people so much. I miss making people smile and laugh. My purpose. This week I learned the word 'mudita' - sympathetic joy, joy from giving others joy. That is me. That is my joy!" she wrote.
Although some were hoping for a Lopez-Affleck reunion, it didn't happen — publicly, at least. (Reports circulated over the weekend they were spending time together again as "friends.") Affleck, who was engaged to his Gigli co-star in the early aughts, did a bit with Jimmy Kimmel instead.
In addition to Lopez, Global Citizen's concert features performances by Foo Fighters, Eddie Vedder, J Balvin and H.E.R. Prince Harry, who appeared in person, was a campaign chair with Meghan Markle.
The "Vax Live" concert will air Saturday on ABC, ABC News Live, CBS, YouTube, iHeartMedia broadcast radio stations and the iHeartRadio App at 8 PM ET. It will run on FOX at 11 PM ET. YouTube will stream an extended version on the Global Citizen channel, which will include additional performances and appearances.
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