The actor, who plays Sam Winchester in the Sky Living series, confirmed the baby news via Twitter in a slightly confusing but quite funny way.
After rumours that Genevieve is pregnant emerged, Jared tweeted: "We got a LOT of questions this weekend about my wife and whether or not we wanted another child. Well, we want everybody 2 know th…"
Three hours later he added: "Shoot! I got on a plane and THEN realised that my tweet wasnt finished!Not used to this 140 character thing. I confirm that Genevieve is pre…"
Just in case anyone wasn't convinced, he later uploaded a photograph of his son Thomas holding a series of ultrascan photos.
He wrote: "Ok, ok! For real: here is Thomas with his future sibling :) (toms the one in the superman shirt)."
Jared and Genevieve, who played the demon Ruby in Supernatural, were seen looking loved-up at the Comic-Con convention in San Diego this weekend, where Jared was snapped with a protective hand on his wife's stomach.
The couple became parents to son Thomas Colton Padalecki on 19 March 2012, and asked well-wishers to donate to a local hospital in lieu of baby gifts.
They've been married since 2010, when they tied the knot in Sun Valley, Idaho.
Congrats to Jared and Genevieve!
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