On May 13, Kateri and Jay Schwandt from Michigan welcomed their 13th son.

In this Aug. 6, 2013 photo, the 12 Schwandt brothers pose for a photograph in their home in Rockford, Mich. Clockwise from bottom left are: Tyler, 21, holding Tucker, 2 days; Vinny, 10; Drew, 16; Zach, 17; Charlie, 3; Calvin, 8; Brandon, 14; Luke, 19 months; Gabe, 6; Wesley, 5 and Tommy, 11.

Chris Clark / AP

"It's a BOY!" Jay wrote in a Facebook post. "BLESSED beyond belief!"

Kateri Schwandt holds her new son, who weighed eight pounds and 15 ounces when he was born at 9:06 a.m.

Jay Schwandt / AP

Before the delivery, the parents, both 40, said they had a tradition of not knowing the child's sex before birth, according to Today. They added that with their luck it would probably be a boy.

"If we were to have a girl, I think we would go into shock," Kateri Schwandt said in October. "It would probably be disbelief."

The odds of giving birth to 13 sons in a row are about 1 in 8,000.