Things got a little hairy between Mick Mulvaney and Trey Gowdy on Tuesday.

It began when Mulvaney, President Trump’s budget director, wished Gowdy, the Republican congressman from South Carolina, a happy birthday on Twitter.

Mulvaney, who is also from South Carolina and served in the House with Gowdy, ribbed the former Benghazi committee chairman over his many hairstyles, tweeting four photos.

“What do you get for someone on his 60th birthday?” Mulvaney tweeted. “A razor and a comb. Happy birthday, @TGowdySC.”

But Gowdy, a former prosecutor, punched back with a reference to the recent White House staff exodus.

“I'm just a couple of haircuts away from equaling the number of staff departures by your WH colleagues,” Gowdy said. “I get it. You are hard to work with.”

The fiscally-conservative Mulvaney then responded: “If I could defund your haircuts, I would.”