Welcome to the world, Prince Alexander Erik Bertil Hubertus!

Just days after Princess Sofia and Prince Carl Philip welcomed their baby boy, the royal couple has released the newborn's name — and we love their son's moniker!

"It's an unexpected choice," royal nomenclature expert Herman Lindqvist told Swedish outlet SVT, according to _ People_. "No Swedish royals have been called Alexander, although during the 1800s, some princes had it as one of their names."

The duo subsequently took to Facebook to share the first photo of little Alexander.

"The Prince's family has now left the hospital and is home at Drottningholm Palace. We're all feeling good and looking forward to [spending] time together," the sweet photo of Sofia and Carl Philip with their baby — who weighed in at 7.9 pounds and measured 19.3 inches long at birth — was captioned on Facebook.

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Sofia, 31, and Carl Philip, 36 — who married in a lavish royal wedding in June 2015 — previously announced they were expecting their first child last October with an official statement released by the Swedish Royal Court. "We are so happy and excited to announce that we are expecting our first child. We are very much looking forward to it," the duo said of Sofia's pregnancy at the time.