Kendra Wilkinson is not a fan of Holly Madison.

The former Playboy “Girls Next Door,” who both dated Playboy founder Hugh Hefner at the same time, have bad blood between them. Their feud reignited on Twitter Thursday when Wilkinson took to the social media site to respond to claims Madison recently made to People magazine.

People published an interview Thursday morning in which Madison opened up about some of her struggles while living in the Playboy Mansion and dating Hefner for seven years. Madison claimed she was “scared” when she first moved in, and that it wasn’t a healthy environment to be in.

“When I arrived, I saw women tell lies about other women and get them kicked out. I got scared really fast,” she told the outlet. “They were always watching every move I made. There were sharks in the water.”

Madison, 36, continued that the women living in the mansion were encouraged to act dumb. She also revealed that the women were made to feel as if their “value” decreased with age, and that Hefner was a “drama queen.”

Wilkinson, 30, responded to Madison’s remarks on Twitter in NSFW, expletive-filled rants. You can read them HERE, HERE and HERE. Madison has not responded to Wilkinson’s tweets.

Madison and Wilkinson, along with Bridget Marquardt, appeared together on the E! reality show “The Girls Next Door” for five seasons from 2005 to 2009. The reality series documented their life as Hefner’s girlfriends living at the Playboy Mansion. By Season 6 their relationship with Hefner had ended, and the show centered on the Playboy founder’s new girlfriends, Kristina and Karissa Shannon and Crystal Harris.

Although Madison, Wilkinson and Marquardt appeared to be friends on screen, Wilkinson revealed after filming concluded that their friendship was fake. More of their fallout was revealed in Madison’s 2015 tell-all, “Down the Rabbit Hole: Curious Adventures and Cautionary Tales of a Former Playboy Bunny.”