Corey Simms Leah Messer
"Teen Mom 2" star Leah Messer (right) reportedly lost custody of her 5-year-old twins, Ali and Aleeah, to her first ex-husband, Corey Simms (left). MTV/Viacom

“Teen Mom 2” stars Corey Simms and Leah Messer have had a rocky relationship since they were teenagers, but things get nasty during Part 2 of the reunion special when Messer hints that her first husband cheated on his current wife, Miranda Patterson. They way she says it, Messer makes it seem like Simms tried to hook up with her.

The drama unfolds when moderator Dr. Drew Pinsky tries to stop Messer, 23, from talking about Patterson since she wasn’t at the taping to defend herself. Messer says she and Patterson “got along great the past two years” and then Simms rhetorically asks, “So what’s the problem?”

Then Simms answers his own question. “It’s because Miranda gave me a backbone to stand up to your bulls---, Leah. That’s exactly what it is,” he says. “Because I don’t care what you think or say.”

When Dr. Drew, who is an addiction specialist and media personality, asks what the true problem is, Simms cites envy. “She’s got issues with Miranda because she’s jealous of Miranda,” Simms, 25, says. “Me and Miranda have a normal, functioning life. She can’t keep a husband for more than two years!”

Get More: Teen Mom 2, Full Episodes

After Simms’ dig at her two failed marriages, Messer denies she’s jealous of Patterson and then insinuates that Simms cheated on his wife in the beginning with her. “Never in my life would I be jealous of Miranda. Where were you at during your first couple months of marriage?” she asks.

It’s not the first time Messer has accused Simms of cheating on Patterson early in their relationship. Recently rumors swirled that Simms and Messer had sex in the back of his truck.

Messer herself isn’t a stranger to rumors, and has been accused of abusing prescription pain pills. On Season 6 of “TM2” she went to rehab, but said it was for anxiety and stress, not drug addiction.

Check out Part 2 of the “Teen Mom 2” reunion special Wednesday at 9 p.m. EDT on MTV.

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