Madonna Attends Beatles Documentary Premiere While in London to Look After Son Rocco

09/16/2016 11:22 am EDT

Just days after her custody battle was resolved, Madonna flew to London Monday to look after her 16-year-old son Rocco as he began his first week of school, but she also found a little time for herself as she attended the premiere of director Ron Howard's new documentary on The Beatles, The Beatles: Eight Days a Week – The Touring Years.

The documentary's premiere was Thursday night, and the singer attended with two friends. The Material Girl sported a black and white varsity dress on the bue carpet, accessorized with a pile of necklaces and a pair of hoop earrings.

Madonna shared several moments from the night on social media, starting with a video of herself and a friend singing The Beatles' "A Hard Day's Night."

"On our way to Beatles Documentary..........feeling inspired!" the pop icon wrote.

She later posted a snap of herself on the blue carpet next to the band's logo, with the simple caption, "Epic!"

Despite the girls' night, sources say the singer's trip to London wasn't all fun, as Madonna allegedly hopped across the pond because she was worried about her son after ex-husband Guy Ritchie left for Los Angeles with his wife, leaving Rocco to start classes alone last week.

Sources say the singer was "deeply worried" about Rocco's lack of parental supervision, as he had previouly damaged his attendance record last year, something Madonna reportedly does not want to happen again.

"Madonna dropped everything in the US and rushed to be with Rocco," a family source told The Sun. "Part of the reason for her agreeing the custody deal was the knowledge that his next school year is crucial for his future. He has important exams coming up."

"So she was deeply worried to learn that he had been left when Guy went off on holiday, the source added. "Any peace and understanding that existed between the parents has been tested by this."

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