Kim Kardashian “Cried” Watching Mason’s Birth on Finale

 John Parra/; Joe Coomber/Sipa Press

Oh, baby!

Kim Kardashian
teared up while watching her nephew, Mason, being born on Sunday night's season finale of Keeping Up With the Kardashians.

See the Kardasian clan's family photo album

"I cried too… sooo emotional," she Twittered after a pal wrote to her that she was getting emotional.

Kim, 29, also joked about hiding in the closet while her big sis Kourtney gave birth last December.

Watch a VIDEO of Kourtney dishing about her pregnancy

"I had to! Too many people in the room," wrote the reality star, who also premiered her new show on E! Sunday night, SPINdustry, for which she's an executive producer.

Kourtney, 30, was also amazed reliving the birth.

See adorable shots of Kourtney and her baby son

"It's so crazy to be watching Mason being born with Mason," she Twittered. "How amazing r these home videos? @ScottDisick and [little sister] Kyle filmed all of it."

On Saturday, Kourtney and Disick left their 2-month-old baby boy home to host the DASH fashion show at JET in Las Vegas.

See what Kourtney looked like pregnant

Kourtney showed off her super slim post-baby body — and denied a report that she had butt implants.

Twittered the reality star, "Hilarious. I did just have a baby 2 months ago, but glad u think I have butt implants. Made me smile,thank u!"

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