Justin Timberlake Wakes Up Wife Jessica Biel by Singing 'Happy Birthday' to Himself - Watch!

Justin Timberlake is celebrating his birthday!

The Man of the Woods singer, who turns 39 on Thursday (January 31), posted a funny clip of himself singing “Happy Birthday” to himself in a car alongside wife Jessica Biel on Wednesday (January 30) while in New York City.

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“Gotta work tomorrow for my bday so wifey really going all out tonight…” he captioned the post.

While he starts off singing quietly, he eventually gets louder and wakes up Jessica.

“I’m just preparing for our big night out!” she laughed.

Watch the funny video below!