The reality star's message to her ex: "I don't really have anything to say to you, so go f--k yourself."
Though Kail had been getting $475 a month from Jo since their son Isaac, now 9, was 8-months-old, Rivera finally turned the tables in a move that made Lowry's "jaw hit the floor."
On Monday, Kailyn got a text from her attorney reading, "I should let you know Mr. Rivera thinks you're a payday for him now that you have shared placement and thinks that he can get over $1,000 a month from you."
Lowry was heated, saying the request came out of nowhere and explaining she recently told Jo she would stop collecting money from him. But the payments from Rivera never stopped, as Lowry said she just "never got around to" canceling them.
While talking over the situation with his wife, Vee, Jo made it clear he definitely felt a certain kind of way about still making monthly payments to his ex.
"I shouldn't be, you're making hundreds and hundreds of thousands of dollars every year," he claimed, "and then you tell me all the money that you make that you don't tell other people about, like $5-10K coming in every month from Instagram just on advertisements."
"For the past 8 years, she's had her hand around my throat, pushing me under the f--king water and just holding me there," Rivera continued. "At this point, I'm entitled to something for this past year of me paying and I'm entitled to the help. I feel like I do need some help."
While Vee said she wouldn't "feel comfortable" taking Kail's money, Jo said it was necessary to give Isaac the same lifestyle he has when he's at his mother's home.
Lowry vented to her friend Becky about the scenario while driving to her lawyer's, saying she was preparing for the worst and not happy about it.
"Just because I make more and you can get it, doesn't mean that that makes it right. I want to see what the expenses truly are," she said. "Maybe he thinks that I'm making millions, but I sure as f--k wouldn't be living in the house I live in, driving a Suburban if I made millions!"
She added, "It's hard to not look at Isaac and be like, 'I hate your dad, don't talk about him.' But I cant, I can't do that."
After consulting with her lawyer, Kail discovered that should could pay upwards of $2,300 a month if Jo's request is approved. Her lawyer added that they'll first have to try to hash things out in mediation, but that idea didn't leave Lowry feeling too hopeful.
"The fact that he wants back child support proves to me that you are looking for a payday, you are not doing this in the benefit of Isaac," she said angrily to her friend over the phone. "You are doing this for the pure benefit of yourself."
"For me, that's greedy and that's selfish and I don't really have anything to say to you," she continued, "so go f--k yourself and all I can do is hope that the judge sees that."
Stay tuned! "Teen Mom 2" airs Mondays at 9pm on MTV.