And the praise comes despite that he does not agree with everything she wrote about their relationship.
"Grab a copy of A Letter of Love if you haven't, I tried to act like I didn't want to read it...but I did lol," Chris tweeted on Sept. 26.
"And even though it's things about me I may not agree with, overall proud of her! I don't know many people that have four published books lol."
Lowry revealed how their relationship soured at one point in her memoir.
"I've had my bedroom window broken while the baby was asleep with me in the room," she revealed in excerpts to RadarOnline.com.
"My back door had been broken while all of my kids were at home. I've had s--t about me told to my children."
The 26-year-old revealed they tried unsuccessfully to reunite after the birth of son Lux in August 2017.
"I've been left to take care of everything," Kailyn wrote.
"Even the responsibility for all of the baby formula was left up to me. Because I can be totally responsible for our child doesn't mean that I should take care of everything."
However, they are now co-parenting and got together for Lux's first birthday.
Her former partner Javi Marroquin was not so complimentary about being talked about in the book.
Lowry revealed that she knew she would regret marrying him.
Marroquin was outrage and tweeted: "Who tf who would write that in a book dedicated to your children.
"Regardless of how our marriage ended stop lying and trying to convince yourself what you did was OK. Forreal I really don't wanna come on here and spill tea because we're past that forreal."
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