The 24-year-old reality star and makeup mogul revealed the news by posting a video to her verified Instagram account, where she shared footage from the early stages of her pregnancy.
Jenner shows a positive pregnancy test to Scott, who then proceeds to hug her belly.
In another scene, Jenner discloses the news of her pregnancy to mother Kris Jenner, who opens an envelope handed to her by Stormi, which contains ultrasound pictures.
“What is it, are you pregnant?,” Jenner’s mother asks her.
“Stormi, we’re going to have a baby,” she adds. “This is one of the happiest days of my life.”
The video ends with a vignette of Stormi kissing Jenner’s baby bump.
Members of the Kardashian-Jenner clan congratulated the couple in the comments section of the video, with sister and model Kendall Jenner saying, “I can’t handle it.”
“Crying!!!!,” Kim Kardashian wrote.
“Crying this is so beautiful my blessed angel sister,” Kourtney Kardashian posted.
“Awwwww,” Khloe Kardashian said.
She did not divulge any other details about her second pregnancy.