Justin Timberlake and Jessica Biel are eagerly awaiting the birth of their first child, but they're apparently holding off on finding out the sex.

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After months of unofficial reports, Timberlake confirmed that Biel is indeed pregnant with an Instagram post on Saturday (his birthday).

"Thank you EVERYONE for the Bday wishes!" the dad-to-be captioned a picture of himself kissing Biel's sizable baby bump. "This year, I'm getting the GREATEST GIFT EVER. CAN'T WAIT. #BoyOrGirl #YouNeverKnow #WeDontEvenKnow #WeAreTakingBets."

Timberlake, 34, and Biel, 32, were married in 2012.

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