TBS late-night star Conan O’Brien hosted Mitt Romney’s five grown sons on his show Wednesday night as the siblings continue their “Dad’s a Prankster” campaign.

The campaign launched in earnest on Father’s Day, when the GOP presidential candidate’s camp released a video in which his sons reminisce about their dad as a great “entertainer” who pulls pranks.

Last month, The Washington Post published an article that recounted an incident in which Romney, while a prep-school senior, marched a posse toward a new student who was “perpetually teased for his nonconformity and presumed homosexuality” and cut the student’s bleach-blond hair. In another incident, The Post reported, Romney shouted “Atta girl!” at the efforts of a then-closeted gay student to speak out in class.

Romney apologized last month for participating in “a lot of hijinks and pranks during high school” and said “some might have gone too far.” He said he does not remember the haircutting incident.

Back to Conan.

“Is one of you a girl being raised as a boy?” Conan asked Romney’s sons early on in Wednesday’s interview.

“Ben, you want to take this one,” said Josh Romney, turning to one of his brother’s.

“Ben — sold out immediately!” Conan snarked, adding, “You’re very attractive, Ben.”

“It’s the purple tie,” Conan sidekick Andy Richter said of Ben’s attire.

Conan O'Brien interviews Gov. Mitt Romney's five sons. (Meghan Sinclair/Conaco for TBS)

“I remember a story from when he was in high school — I guess a little after high school,” brother Tagg began.

This story involved Dad breaking into a pal’s hotel room before the friend’s wedding and, in pink nail polish, writing “HELP” on the soles of the guy’s shoes — so that when the pal kneeled for a blessing at the ceremony, the audience saw the word.

The Romney sons came prepared with an audiovisual aide: a video of an incident in which they pretended to be then-California Gov. Arnold Schwarzenegger (R) in a phone call with their dad, who was trying to land the governor’s endorsement. In the video, Romney at first appears to believe that it’s Schwarzenneger on the phone — until the phone voice says that he’s going to ask Romney a bunch of questions and begins with: “Who is your daddy, and what does he do?”

Romney is seen hanging up.

The Romney sons also had a story about their dad’s penchant for holding up food items that he says are rotten and asking someone to smell them, then pushing the person’s face into the food.

“And you go down, and, right into the butter. Or the whipped cream,” brother Matt explained to Conan. “You’re ending up with stuff all over your face.”

“Wait a minute, okay, so he’s basically just smashing your faces into food all the time?” Conan asked.

“If he was the president, would he be saying, ‘Hey, Mr. Bernanke, I’m worried about these figures’ — mush?” Conan asked, worried. But not so worried that he waited for an answer, immediately adding, “We should take a quick break.”

Here’s the rest of their appearance: