The Originals actor, 39, said it took days after their son was born on April 4 to settle on the perfect name for their progeny: Theodore Vigo Sullivan Gillies.
“We just couldn’t settle on a name because it’s such an important decision,” the actor tells PEOPLE, explaining that he went with nicknames including “sweetheart,” “raisin” and even “calcified alien” in the interim.
The couple had it narrowed down to two names before birth — after compiling individual lists that included upwards of 700 names to start, then creating a sort of “Venn diagram” to see which names overlapped between them, before coming up with their top choices.
“Even after he was born we couldn’t determine whether or not he was Theodore or Vigo, because he was just so beat up from [being born],” he says. “Some might say he should be Vigo because of Viggo Mortensen, kind of battle-scarred. But there was something so adorable about him.”
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