The Keeping Up With The Kardashians star and long-time boyfriend Scott Disick welcomed their second son on Sunday, 14 December.
And if that date seems familiar, it's because it's the same day as their son Mason's birthday!
Yep! Kourtney gave birth to her third child on Mason's fifth birthday!
A rep for the couple confirmed the birth but have not revealed the name.
Kourtney was believed to have been due around Christmas Day but, as happened with Mason, the baby arrived early.
She had joked recently she'd be keeping her doctor "handcuffed" to her throughout the Christmas holidays... well, it looks like she won't have to now!
Speaking about her pregnancy last month, the 35-year-old said: "I love being pregnant in general. This time, I'm more tired than I was the other times. I think it's because I'm always running around and working on different things.
"But I feel comfortable with how I look and feel. I find a pregnant body to be beautiful and an incredible reminder of what a woman's body is made to do."
Kourtney and Scott are also parents to daughter Penelope, two.
As with her previous pregnancies, this one has been documented on the family reality shows including Keeping Up With The Kardashians and Kourtney & Khloe Take The Hamptons!
It was in the latter show last week we discovered Kourtney was expecting a boy.
We saw a home video made by Kourtney's sister Kim Kardashian, in which little Mason was brandishing a stick with a blue star on it. Blue for a boy!
Congrats to Kourtney and Scott!
More stars who welcomed babies in 2014!
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