(CNN) Wisconsin Republican Sean Duffy announced Monday that he will resign from Congress next month, joining nine other House Republicans who have announced their own planned departures in recent weeks.

Duffy, a Trump ally who has represented Wisconsin's 7th district since being elected in 2010, wrote in a Facebook post that he would be stepping down on September 23, citing a desire to spend more time with his family ahead of the upcoming birth of his ninth child. Duffy said he and his wife, Fox News contributor Rachel Campos-Duffy, learned there were complications with the pregnancy.

"Recently, we've learned that our baby, due in late October, will need even more love, time, and attention due to complications, including a heart condition," he wrote. "With much prayer, I have decided that this is the right time for me to take a break from public service in order to be the support my wife, baby and family need right now."

Reid Magney, a spokesman for the Wisconsin Elections Commission, told CNN that Gov. Tony Evers, a Democrat, cannot call a special election until the office is officially vacant. There's no law as to how much time the governor must wait to issue the order once the seat is vacant. The date of the special election must be within roughly three to four months of the governor's order.

Duffy, formerly a professional lumberjack athlete and ESPN color commentator, was district attorney of Ashland County, Wisconsin from 2002-2008, before seeking and winning election to the House in the GOP wave of 2010. In 2018, he handily won reelection by 22 points.

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