A big congratulations might be in order for Kourtney Kardashian and Scott Disick after they reportedly welcomed a baby boy on Mason Dash’s birthday, People reported Sunday. While the Kardashian family members remained silent about their newest family member, whose name has not been revealed, they made sure to take to Instagram and Twitter to wish their nephew a happy birthday.

Kourtney Kardashian:

Even though she just gave birth, the oldest Kardashian sister made sure she remembered Mason on his fifth birthday.

Kim Kardashian:

Kim, whose daughter North West is now 18 months, referred to her nephew as the “Lego master.” She shared a personal photo of the two together and expressed her love for Kourtney’s 5-year-old.

Khloe Kardashian:

Khloe, the youngest Kardashian sister, can’t believe how fast Mason is growing up. She used two of his nicknames, Mase and Ace, to wish him a happy birthday. “Stop growing up!” she exclaimed.

Kendall Jenner:

The reality star turned model also couldn’t believe how fast time went when she gave little Mason a shout out on Twitter. “He’s 5 and I can’t take!” she shared.

Kris Jenner:

Mason’s grandmother and the matriarch of the Kardashian family referred to her grandson as her “precious little Mason.” For her Instagram post, she added the hashtags “blessed” and “family.”

Kylie Jenner and Rob Kardashian didn’t take to Twitter or Instagram to share anything for Mason’s birthday online -- but they weren’t the only ones. Disick, who is now a father of three, remained silent on social media following the birth of his youngest child.

“I’m so happy we’re having a boy,” Kardashian said on “Kourtney & Khloe Take the Hamptons.” “It’s going to be perfect for our family.”

Further information about the baby has not been revealed. Kardashian and Disick also are parents to Mason Dash, 5, and Penelope Scotland, 2.

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