EXCLUSIVE: Justin Timberlake Says Son Is 'Everything,' Explains Why Jessica Biel Is Missing From 'Trolls' Musi

The 35-year-old superstar is promoting his family-friendly project with Anna Kendrick in Cannes.

Justin Timberlake is one proud papa!

The 35-year-old superstar couldn't help but gush over his baby boy Silas at the Cannes Film Festival, where he's promoting Trolls with co-star Anna Kendrick.

"I've been just showing Anna videos over and over again," Timberlake told ET's Carly Steel, while Kendrick joked that the constant Skyping with his 1-year-old baby boy was "so annoying."

"This is tough," Timberlake admitted. "I mean, Cannes Film Festival is amazing, but my son is everything."

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But at least he's in good company! Kendrick opened up about why Timberlake has been such a great travel buddy.

"Sometimes this is a little bit crazy and it's good to have kind of a practical partner in crime, because sometimes actors can be crazy," she said. "And musicians, even more so, even though I know fewer. But Justin is just a practical person and a good person to have on your team when you're facing this kind of craziness."

Last week, Timberlake unveiled his latest studio effort, "Can't Stop the Feeling." The song is featured as the first single from the Trolls soundtrack, for which the nine-time GRAMMY winner also served as executive music producer.

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"Can't Stop the Feeling" made its web debut with a delightfully starry dance video, featuring Kendrick, James Corden, Gwen Stefani, and more cast members from the film. But we were definitely holding out hope for a cameo from Timberlake's wife of three years, Jessica Biel!

"She was busy that day," Timberlake said with a laugh. "There's actually sort of an official video coming in a week’s time, probably, directed by Mark Romanek. I think you'll enjoy that one, as well."

WATCH: Justin Timberlake Calls Jessica Biel 'MILF,' Shares New Photo of Son, Silas