Supernatural star Jensen Ackles is about to step into his biggest role yet: dad.

The 34-year-old actor and his wife, One Tree Hill actress Danneel Harris, are expecting their first child later this year, his rep confirms to Us Weekly.

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"Thank you for all the well wishes," the mom-to-be tweeted on Jan. 7. "We are very excited about our soon to be new addition."

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Harris, 33, who also starred in the short-lived sitcom Friends With Benefits, accepted Ackles' proposal in 2009 after three years of dating. The couple married in 2010 in the former Days of Our Lives actor's hometown of Dallas, Texas.

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Incidentally, the Supernatural family welcomed another little bundle of joy just last year, when Jared Paledecki (who plays Ackles' onscreen brother) had a son, Thomas Colton, with wife Genevieve Cortese on March 19.

This article originally appeared on Jensen Ackles Expecting First Child With Wife Danneel Harris