Kailyn Lowry Claims Ex Javi Marroquin Was Cheating on His Fiancée During Her Pregnancy

Kailyn Lowry is making a major allegation about ex-husband Javi Marroquin.

On Tuesday night’s Teen Mom 2, the mother of three, 27, claimed Marroquin, 26, had been unfaithful to his fiancée Lauren Comeau.

Lowry made the allegation after an MTV producer, Patrick, approached her with a photo of Marroquin and Comeau as they revealed they were both engaged on Instagram.

“Did you see this? Javi and Lauren are engaged,” Patrick told Lowry, who responded, “Yes, I already knew it was happening. I didn’t know he actually did it but I knew it was going to happen.”

Patrick asked: “Oh, are you going to congratulate them?”

Laughing, Lowry said, “No,” before adding, “Congrats! Good luck, he’s been cheating on you since you were pregnant.”

Marroquin did not immediately respond to PEOPLE’s request for comment.

Marroquin and Comeau share one son together, Eli, 10 months, whom they welcomed in November 2018. He also has son Lincoln, 5, with Lowry.

Earlier in the episode, Lowry alleged Marroquin had shown up outside her New York City hotel room as they were filming the Teen Mom 2 reunion earlier this year.

RELATED: Javi Marroquin Apologizes to Fiancée Lauren Comeau: ‘I’m Sorry I Disrespected You’

In a previously unseen moment that was filmed at the time of the reunion and aired on Tuesday’s episode, Lowry could be heard telling her costar Leah Messer, “Javi came to my room at 6:30 this morning. Knocking at my door. I literally opened the door and I was like, ‘What the f—?’ ”

“I wonder why he came?” Messer asked.

Lowry claimed, “He tried to f— me, and I was like no.”

During Tuesday’s episode, Lowry addressed the moment with Vee Torres, the wife of Lowry’s ex-boyfriend Jo Rivera, telling her that Comeau had attempted to reach out to her to discuss her claims about Marroquin.

View this post on Instagram June 17th I asked my best friend to marry me. @lauren3elizabeth Our sleepless (mainly yours) nights… our endless laughs… and our countless jokes to each other now can be forever. Without you, our gym wouldn’t be possible. Without you we wouldn’t have a place to call home. Most importantly, without you, we wouldn’t be complete. Thank you for being the greatest mom to Eli and now (soon to be) stepmom to Lincoln. I feared not finding someone that would love me and linc the way you do. Never have I questioned that with you. Thank you for everything you do for this family. I can’t believe I’m this lucky.

A post shared by Javi Marroquin (@javim9) on Jun 18, 2019 at 1:59pm PDT

//www.instagram.com/embed.js

View this post on Instagram I love you and I’m sorry.

A post shared by Javi Marroquin (@javim9) on Aug 26, 2019 at 11:07am PDT

//www.instagram.com/embed.js

“Lauren wanted to call me after that stuff aired on TV. I think he played it off, I don’t know. I don’t know,” Lowry told Torres. “I said I wouldn’t talk about it.”

“He’s told me that he really wants to propose to her. If she trusts him, then good for her,” Lowry continued. “I don’t wish anything bad on them, I really don’t. It’s not like I want to be with him.”

In August, Marroquin posted a lengthy apology to Comeau on Instagram in which he said he was “sorry I disrespected you.”

While the CrossFit gym owner didn’t go into detail about their alleged fight, he did write, “I’m sorry I took you for granted. I could say sorry for a million other things but I’m sorry will never be enough. I hurt the one person that I love the most. I will do everything in my power to become a better man and hopefully one day you can forgive me.”

RELATED VIDEO: Teen Mom Star Javi Marroquin Shares Apology to Ex-Wife Kailyn Lowry for Briana DeJesus Drama

He then suggested that Comeau was not currently living with him, adding, “I’ll do anything to have you home.”

A day before his apology, Comeau seemed to address the mysterious drama between them, and quoted Shannon L. Alder on Instagram, writing, “To be a mother of a son is one of the most important things you can do to change the world. Raise them to respect women, raise them to stand up for others, raise them to be kind.”

While the specifics of their fight are unclear, Radar Online reported in August that Comeau allegedly discovered Marroquin with a naked woman in their home after he threw a party.

Marroquin did not respond to PEOPLE’s request for comment at the time.

Teen Mom 2 airs Tuesdays (8 p.m. ET) on MTV.