Kim Richards' Daughter Brooke Wiederhorn Gives Birth to Her First Child!

Kim Richards is a new grandma!

A source tells ET that Brooke Wiederhorn, daughter of the former Real Housewives of Beverly Hills star, gave birth to a baby boy on Wednesday.

The adorable new addition to the family is the first child for Brooke and her husband, Thayer Wiederhorn, and is Richards' first grandchild.

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A week before Brooke delivered her baby, she took to Instagram to celebrate her mom's 52nd birthday, where she gushed over how wonderful the reality star is going to be as a grandmother.

"Happy birthday to the most amazing mom in the world! I know you will be an even more amazing grandma!!" Brooke, 30, captioned a sweet mother-daughter snapshot. "I love you!"

Happy birthday to the most amazing mom in the world! I know you will be an even more amazing grandma!! I love you! ��������������������������������

A photo posted by Brooke Wiederhorn (@brookewiederhorn) on Sep 19, 2016 at 4:29pm PDT

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Brooke, whose father, Monty Brinson, died after a long battle with cancer back in January, announced she were expecting back in March.

"Happy Easter," she wrote alongside a photo of tiny baby clothes inside of an Easter basket. "Can't wait to meet our baby BOY!"

Happy Easter��������! Can't wait to meet our baby BOY! ����������������

A photo posted by Brooke Wiederhorn (@brookewiederhorn) on Mar 27, 2016 at 1:02pm PDT

Brooke snapped a number of photos of her growing baby bump over the course of her pregnancy, which she shared to Instagram to document her journey.

Pool day with my sister ��������

A photo posted by Brooke Wiederhorn (@brookewiederhorn) on Jun 19, 2016 at 9:51pm PDT

Bumping around the city ����

A photo posted by Brooke Wiederhorn (@brookewiederhorn) on Jul 23, 2016 at 12:54pm PDT

I can't wait to meet you little one ������������ #BumpDay

A photo posted by Brooke Wiederhorn (@brookewiederhorn) on Aug 3, 2016 at 3:31pm PDT

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Two weeks ago, she bared her belly in this heartwarming black-and-white photo, which she captioned, "Mommy & Daddy Can't Wait To Meet You!"

Mommy & Daddy Can't Wait To Meet You! ����������������

A photo posted by Brooke Wiederhorn (@brookewiederhorn) on Sep 14, 2016 at 12:10pm PDT

Back in August, Richards took to Instagram to share a photo of her kissing her daughter's stomach, and marveled in the caption, "It's amazing how much we love him already."

It's Amazing how much we love him already���������������� as I look at this picture, I see his ����Mommy looking down with so much love������ Grandma , kissing & holding him already.. And Auntie Whitney can't get close enough!! Soo much love������ won't be long now till he's in Our Arms!! #love #mommy #grandma #auntie #babyboy @brookewiederhorn @whittlesdavis

A photo posted by Kim Richards (@kimrichards11) on Aug 30, 2016 at 1:39pm PDT

Congrats to the happy couple and the brand new grandma!

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