Kloss first revealed that she was expecting her second child while at the Met Gala in May.
Karlie Kloss is introducing the world to her baby boy!
After the supermodel's husband, Joshua Kushner, took to Instagram to reveal that the pair had welcomed their second child last week, Kloss shared a follow-up post on Thursday that revealed their son's name.
The sweet black-and-white photo showed their newborn son gripping the finger of his 2-year-old brother, Levi, while lying with his eyes closed.
Kloss captioned the post, "Elijah Jude 7.11.23."
Kushner first shared a photo of the newborn, who appeared fast asleep and bundled up in a blanket, on July 13, when announcing his arrival.
While it wasn't a full look at the little one, the photo did feature their new addition in an adorable blue beanie.
"welcome to 🌎❤️ 7.11.23," Kushner captioned the post.
The announcement was met with lots of love in the comments, with Gwyneth Paltrow, Kim Kardashian and Kate Hudson all sharing words of congratulations.
While Paltrow simply left behind a red heart emoji, Kardashian commented, "Congrats!!!! ❤️," and Hudson wrote, "🙌🙌🙌 Welcome!!!🙌🙌🙌."
Kloss' sister, Kimby, also commented on the post with her own trail of excited emojis, "🥰❤️🙏."
Kloss revealed that she was pregnant with baby no. 2 while at the Met Gala in May. The 30-year-old runway star put her bump on display in a black, long-sleeved Loewe gown which she accessorized with a bevy of pearl necklaces strung around her neck. She also added a few just below her pregnant belly, highlighting her growing baby bump.
While she usually rocks a shorter, blonde 'do, Kloss opted to wear her long, brown locks in a low ponytail, which she topped with a big, black satin bow.
ET spoke to Kloss about why she chose to reveal her pregnancy at the Met Gala, and how she kept it under wraps for all this time.
"This is the most important night in fashion, of course, and I'm honestly surprised I could keep it a secret this long," Kloss said of why she decided to debut the news during fashion's biggest night.
As for how she kept her bump a secret, Kloss said "big winter coats" did the trick.
Kloss and Kushner -- whose brother is Jared Kushner, the husband of Ivanka Trump and son-in-law to Donald Trump -- have been married since October 2018. The couple got engaged in July of 2018 after six years of dating and welcomed their first child in March 2021.