We’re getting some insight into what led to Kyle Richards and Mauricio Umansky‘s separation.

During the Wednesday night (November 1) episode of The Real Housewives of Beverly Hills, Kyle, 54, revealed a secret about Mauricio, 53, that left him infuriated.

Keep reading to find out more…

In the episode, Kyle and Mauricio hosted a birthday dinner for their youngest daughter Portia‘s 15th birthday with Mauricio‘s parents in attendance.

“Do your parents know I have a tattoo, and you have one too?” Kyle whispered to Mauricio, who replied, “No.”

Later, Kyle revealed to Mauricio‘s mom Estella Sneider that she has tattoos. Tattoos are traditionally forbidden in the Jewish culture and Mauricio, his parents, and Kyle are all Jewish.

Estella confirmed that she has no issues about the ink, but did question Kyle, asking, “Didn’t you do a tattoo for Mauricio?”

Kyle replied, “Did I put his name? No. That’s a jinx anyway.”

She then asked Estella, “Do you know your son has one?”

Later, Kyle told Mauricio that she told his mom about his tattoo, and he was not happy with her making that revelation.

“What is wrong with you?!” Mauricio said, visibly upset.

Kyle tried to reassure him that his mom didn’t care about the tattoo, but he still wasn’t happy with Kyle telling his mom.

“But still, why would I not be allowed to do that?” Mauricio asked. “What is up with that?”

In a confessional, Kyle admitted that she regretted telling her mother-in-law about Mauricio‘s tattoo.

“Why did I open my mouth?” Kyle said. “I thought, ‘Oh, OK, it will be funny in the moment. Wait to see her reaction.’ But now, his reaction, I really wish I had not said anything.”

Earlier during the diner, Estella confronted Kyle about all the rumors she’s been reading online about issues in her and Mauricio‘s marriage, especially after Kyle was photographed not wearing her wedding ring. Kyle reassured her mother-in-law that everything was fine between her and Mauricio.

However, in a confessional, Kyle admitted, “I’m very taken aback that my mother-in-law is asking me this right now tonight. Yes, Mo and I have been having a hard time, but the picture of me without my ring has nothing to do with that. I’ve still been wearing a wedding band.”

It was revealed over the summer that Kyle and Mauricio and separated after 27 years of marriage.

While appearing on WWHL last week, Kyle shared new details about the split, including who initiated it.