The actor -- who shares a 2-year-old son with Leslie -- joked that he's "terrified" about becoming a father of two.
Congratulations are in order for Kit Harington!
During an appearance on Friday's episode of "The Tonight Show Starring Jimmy Fallon," the actor revealed he and his wife, Rose Leslie, are expecting their second child together. The couple is already parents to a 2-year-old son.
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While chatting about his son with Fallon, Harington dropped the surprising news of Leslie's pregnancy.
"He's about to get the shock of his life, which is that he's about to get a brother or sister," he said. "The Tonight Show" audience cheered in response, and Fallon shook his hand.
The "Game of Thrones" alum went on to share his thoughts about becoming a father of two.
"I'm terrified. You know, with the first baby you're like walking on clouds and dancing through fields of daisies for nine months -- well, the man is anyway," Harington quipped. "But this time, the reality check comes much shorter. You get practical real quick."
As for how his 2-year-old son is feeling about becoming a big brother, Harington said, "I'm not sure he's quite conceptually understood it just yet."
"We're trying to get him ready for it," he shared. "We point to Rose's tummy and we say, 'Mommy's baby, mommy's baby.' And he points to his tummy and goes, 'My baby.' I'm quite sure that's -- yeah, you'll know soon enough."
Earlier in the interview, the "Eternals" star spoke more about his and Leslie's first child.
"We think he might be quite smart," Harington said. "It's surprising, seeing as we're both actors. We're like, we're not sure quite where that's come from ... He loves applause. Every time he does something good, we give him applause, and we're worrying that's kind of pushing him towards acting."
He added, "We're a bit like, 'Eh, you might be too smart for this. Go save the world, we're sick, we had no choice.'"
In September 2020, Harington, 36, and Rose, 35, revealed they were expecting their first child. The following February, it was reported the two had welcomed their baby boy.
The couple first began dating back in 2011 after meeting on the set of "Game of Thrones." Harington and Leslie announced their engagement in September 2017, and tied the knot in June 2018.