From Sister, Sister to Mommy, Mommy!

On Monday Nov. 12, Tamera Mowry followed in the footseps of her sister Tia -- becoming a mother for the first time when she and husband Adam Housley welcomed son Aden John Tanner Housley.

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Little Aden will have an instant buddy in cousin Cree Hardrict -- whom Tamera's twin sister, Tia, welcomed back in June 2011 with actor husband Cory Hardrict.

"I am so thrilled and happy to be an Auntie!" Tia, 34, tells Us Weekly exclusively of Aden's arrival. "I now know the love that my sister has for Cree, it is overflowing."

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Former child stars from their 90s sitcom Sister, Sister, the twins are now the stars of their own reality series on the Style Network, Tia and Tamera.

Adds Tia of her brand-new nephew: "I've kissed her new bundle of joy at least one hundred times! I couldn't be happier for her." 

VIDEO: Tamera tells Us about giving up her closet for her baby's nursery

Born in Los Angeles, Aden weighed in at 9 pounds, 5 ounces. Tamera wed FOX News correspondent Housley in May 2011.

This article originally appeared on Tia Mowry: "I Couldn't Be Happier" for Tamera and Her Baby!