Jay and Kateri Schwandt welcomed their 13th son on May 13. Credit: Chris Clark/The Grand Rapids Press via AP

Boy, oh boy, oh boy, oh boy . . .! When Michigan dad Jay Schwandt learned his wife Kateri was expecting the couple's 13th (!!) child, he sincerely hoped it was a girl. Why? The family already has 12 other sons!

To dad's (minor) dismay, Kateri, 40, gave birth to their newest son on Wednesday, May 13, according to ABC News. The Rockford, Mich., couple followed their family tradition of not learning the baby's gender until birth. Though he was hoping — and his wife incorrectly predicted — they'd welcome a girl, Jay isn’t totally broken up over it. "Being a dad, having 12 boys, one more boy is pretty cool," Jay said before welcoming No. 13.

Asked in a Good Morning America interview before their mom gave birth, Tyler, 22, Zach, 19, Drew, 18, Brandon, 16, Tommy, 13, Vinnie, 12, Calvin, 10, Gabe, 8, Wesley, 6, Charlie, 5, Luke, 3, and Tucker, 9 months, were asked who wanted another brother in the family; only three raised their hands.

Weighing almost 9 lbs., and 22-inches long, baby boy Schwandt has yet to be named by his parents - and their other sons.

Mom is understandably overwhelmed, but told GMA she's feeling "pretty good" after her delivery.

"There's a lot of activity, a lot of commotion, a lot of chaos, but there's also a lot of love," Kateri said of raising such a large family, a la the Duggars.

Might there be a baby Schwandt 14? "You never say never," dad hinted.

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