Morgan, née Olsen, and her husband Joel have called their daughter Georgia and she was born on their wedding anniversary.
Announcing the news, Morgan said: "Introducing our sweet Georgia! 9lbs 11oz, 21 inches. Born 9.24.16 (our anniversary) We are smitten #lovechild."
The couple have now shared several pictures of their little girl on Instagram, including a beautiful shot of older brother Theo giving her a cuddle.
Captioning the shot, Morgan - who starred in Laguna Beach alongside Lauren Conrad and Kristin Cavallari - Instagrammed: "And then my heart exploded! Can't get over ... they're both mine!! #siblings."
Well they certainly make gorgeous kids, don't they?!
Earlier this year, Morgan joined some of her Laguna Beach co-stars for a reunion with E!. Morgan's best friend Christina Schuller took part, along with Jason Wahler, Alex Murrel and Taylor Cole from series two.
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