Home design maven Joanna Gaines is expecting her fifth baby with hubby Chip Gaines, the Fixer Upper couple announced on Tuesday, Jan. 2 with a goofy “party of seven” Instagram pic. And if these two HGTV stars need any tips on parenting a big brood, they need only ask Jo’s little sister, Mary Kay McCall, who had five kids already, and welcomed a sixth on Thursday, Jan. 4!

Mary Kay and her husband recently moved back to her family’s hometown of Waco, TX, and their “fixer upper” home renovation is the subject of this week’s episode. “Today’s house was my all time favorite #FixerUpper,” Joanna wrote in an Instagram caption in September. “We got to reveal this house to my sweet sis and her family of seven (going on eight!). I can’t contain the excitement — after nine years they are finally coming back to Waco!”

That’s right, Mary Kay was pregnant with her sixth child while Joanna is pregnant with her fifth, and Joanna was head-over-heels for the little one immediately after it was born on Jan. 4. "My sister had her beautiful baby girl! #motherofsix #butshelooks16 ?," she gushed, aong with some sweet pics. So cute!

Joanna and Mary Kay also have an older sister, Teresa Criswell, who hosts a YouTube show called Let’s Talk with Teresa Ann and writes faith-based posts on her blog Triumphant Victorious Reminders — and the three sisters hang out all the time! Joanna posts Instagram photos of Teresa and Mary Kay on the regular (including plenty of cute throwback pics) and they all seem super supportive of one another.

Take this birthday message from Teresa to Joanna, for example: “Jojo, you are a first class peacemaker with a generous spirit, a heart of gold who has an ability to gather like I’ve never seen!” Or the congratulatory post Joanna wrote to commemorate the birth of Mary Kay’s fifth child: “My sister shines, and I’m so proud of her!” Clearly the Magnolia family tree is a strong one!

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Sister love. #nationalsiblingday ❤️

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