“Teen Mom 2” star Kailyn Lowry feuded with former friend Christina “Peach” Pietrobon Monday in a Twitter fight. The drama erupted after Peach made fun of Lowry for getting plastic surgery and undergoing a Brazilian butt lift.

“At least my nectarine a-- ain't fat and unnatural,” Peach, the name she is best known by, tweeted Monday.

Lowry promptly responded. “Get her nectarine a-- outta here,” she wrote. “It's my own fat... so technically.... nvm.”

Next, Lowry shared notes Peach wrote when they were still friends. In the old messages, Peach told Lowry how much she loved her and appreciated their friendship.

The two ended their friendship last year after Lowry divorced from ex-husband Javi Marroquin and Peach sided with him. Lowry apparently cheated while Marroquin was overseas in the Air Force.

“I never did anything to YOU. You chose a side when we all could have been civil,” Lowry tweeted. “So you decide to hate me for something that didn't involve you? And still doesn't???”

But Peach maintained that she looked out for Marroquin. “ Soooo if someone hurt your best friend you wouldn't be pissed off !? You wouldn't be mad,” she wrote. “It's funny how a "used to be" friend tries to make this all about something it's not. We had problems long before this whole marriage issue.”

The MTV star ended the feud with a general tweet to all her followers. “Didn't know you disown people for their mistakes... that don't even affect you but it is what it is,” Lowry said. The post was liked more than 1,500 times by her 1.23 million followers.

Marroquin wanted to tell his side of the breakup and wrote a book, which is called, “Heartless Hustled.” It’s a riff on Lowry’s “Heart & Hustle.”

“It’s actually a response to Kail’s new book coming out,” the 24-year-old told Radar Online in August. “Except mine will be the truth and what she actually did that ended the marriage.”

A release date was not revealed.

Lowry, 24, is pregnant with her third child. She did not reveal the father of baby No. 3, but it's unlikely Marroquin fathered the child.

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