Former Twilight Star Jackson Rathbone and Wife Sheila Welcome a Son: 'Happiest New Year!'

Jackson Rathbone is a father of three!

The musician and Twilight star, 35, announced on Instagram Wednesday that he and wife Sheila Hafsadi had welcomed their third child, a baby boy.

“Happiest New Year!!!” Rathbone captioned a side-by-side photo set showing a pregnant Hafsadi on the left and her holding their newborn son on the right.

One day later, the actor shared a sweet snapshot of him holding the newest addition to their family, writing alongside it, “Dad x 3 = 🥰.”

The couple’s latest bundle of joy joins big sister Presley Bowie, 3½, and brother Monroe Jackson VI, 7½.

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A rep for Rathbone confirmed the pregnancy exclusively to PEOPLE in June, with the couple, who wed in 2013, telling PEOPLE, “We are over the moon for this new addition to our family, and are excited to soon be a party of five!”

Shortly after the birth of his daughter Presley in 2016, Rathbone told PEOPLE that he and Hafsadi were “open” to having more children.

“We’re going to take some time,” the actor said. “In a hypothetical sense, sure, why not? We’re open to multiple ways of having kids.”

Of his first two children, Rathbone added, “Having a boy first and then a girl, I think it’s going to make [Monroe] a better man when he grows up.”

RELATED VIDEO: Meet Jackson Rathbone’s Son Monroe!

Multiple members of Rathbone’s Twilight family commented on his Instagram posts announcing the birth of his son, like Kellan Lutz who wrote, “Congrats brother!!!!”

“Ah! We love you guys!!!! Congrats!!!” Nikki Reed remarked. “Also, how do all of your babies have the same face?! 😍😍😍😍😍😍.”

“Amazing. 🎉🎉🎉congrats brother,” said Peter Facinelli.