“Teen Mom 2” star Jenelle Evans has pledged that she is clean after becoming pregnant with her second child. But the topic of substance abuse arose during a heated argument between her mother Barbara and her boyfriend Nathan Griffith.

In a preview for Tuesday’s episode on MTV, Barbara and Griffith start to fight after the elder Evans warns her daughter not to let her new beau drive her car since her estranged husband, Courtland Rogers, was just released from prison. Barbara adds that Evans’ past boyfriends have wrecked her cars, according to MTV's Remote Control, and she doesn’t want there to be any altercation between Rogers and Griffith. He takes offense at the warning, as if she were comparing him to the previous men Evans has dated. That’s when things begin to get ugly.

Griffith, feeling defensive, attacks Barbara’s parenting skills. He claims it was the lack of structure that she provided for Jenelle, which ultimately led her to use heroin. Barbara become beyond irate and yells, “I didn’t stick the needle in her arm!”

But overcoming a heroin addiction usually isn’t as simple as Evans makes it seem. In September 2013, the Daily Mail wrote Evans had tweeted that her habit used to cost her $400 daily. She told her followers, “Addiction is a disease.” But she made sure to add, “I’m sober now.” In April of that year she was arrested for possession of heroin, prescription drugs, drug paraphernalia and assault of Rogers.

“Teen Mom” Amber Portwood, who said in the past she was high almost every time she filmed MTV reality series, finds it hard to believe that Evans is sober now. She told Life & Style magazine, “"It's not like you can wake up one day and be like, Hey, I'm clean.'”

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