Kailyn Lowry and Chris Lopez have feuded on and off since the "Teen Mom 2" star welcomed their son, Lux Russell, in August of last year. However, on Twitter this week, they appeared to be on great terms as Lopez spoke out to promote his former girlfriend's new Book, "A Letter of Love."

"Grab a copy of ['A Letter of Love'] if you haven’t," he tweeted, according to a report shared by OK! Magazine on September 28. "I tried to act like I didn’t want to read it...but I did lol," he added.

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Lopez went on to say that while he doesn't agree with absolutely everything Lowry said in the book, he's proud of her and all the things she's accomplished in recent years. "And even though it’s things about me I may not agree with, overall proud of her!" he told his Twitter fans and followers days ago.

"[I don't know] [about] y’all but I don’t know many people that have four published books lol."

Kailyn Lowry and Lopez began dating one another in 2016 after she and her now-ex-husband, Javi Marroquin, called it quits. However, just months into their relationship, as Lowry discovered her pregnancy, she and Lopez ended their romance and she was left to go through her pregnancy alone.

Kailyn Lowry chronicled her pregnancy in 'A Letter of Love'

Throughout the book, Kailyn Lowry opened up about the violent behavior she experienced at the hands of an ex-boyfriend but didn't say which ex she was referring to. "I’ve had my bedroom window broken while the baby was asleep with me in the room," she wrote in an excerpt shared by OK! Magazine. "My back door had been broken while all of my kids were at home," she continued, "and I’ve had s**t about me told to my children."

"I don’t care if the baby is six weeks or six years old," Lowry added, "a dad should not talk down about the mother of his child."

Chris Lopez doesn't want to be a reality star

Although he didn't hesitate to engage in a relationship with longtime reality star Kailyn Lowry, Chris Lopez has never allowed himself to be seen on the show.

While he did film a few scenes, years ago, he was sure his face was blurred out of the final footage and has refused to take part in the reality series ever since. Meanwhile, Lowry has continued to chronicle her life as a single mom and three sons, all of whom have different fathers, with her family and her friends.

"Teen Mom 2" season nine will air sometime later this year or early next year on MTV. A premiere date has not yet been set by the network.