• Justin Timberlake turned 38 years old on Thursday.
  • He shared a video of himself, quietly singing, “happy birthday to me” – then pans to his wife, Jessica Biel, who was fully asleep in the car.
  • “Gotta work tomorrow for my bday so wifey really going all out tonight,” Timberlake wrote in the caption.
  • “I’m just preparing for our big night out,” Biel jokes to the camera after waking up.

Justin Timberlake turned 38 years old on Thursday, but his wife Jessica Biel may not have been fully prepared to help him celebrate.

The “Filthy” singer shared a video of himself in a car Wednesday night, quietly singing, “happy birthday to me.” He then panned to Biel, who was sitting next to him fully asleep.

“Gotta work tomorrow for my bday so wifey really going all out tonight,” Timberlake wrote in the caption.

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After Timberlake made his voice slightly louder and Biel woke up, she laughed.

"I'm just preparing for our big night out," Biel joked, which led Timberlake to make a skeptical expression.

Read more: Jessica Biel took on Jimmy Fallon in a 'Best Friends Challenge' to prove she knows her husband, Justin Timberlake, better

The happy couple met in 2007 and has been married since 2012. They share one child, their 3-year-old son Silas, although they've both been open about wanting more kids.

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During an interview with Apple Music's Zane Lowe last year, Timberlake said he wants to have "as many kids as we can."

"I feel like the success of parenthood is feeling like I failed all day today, but I get to wake up tomorrow and do it again," he said, "and hopefully they turn out to be a good human being."

"My wife and I - when we have a night off and we get into bed and we sit down and watch a movie or something, we're like, 'What did we do before this?'" he continued. "'Did we go out to dinner? Were we at a bar? What did we do before this?'"

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