Kim Kardashian says Tristan Thompson will "never change" while he cheats on Khloe

The episode of Sunday night The amazing Kardashian family prompted fans to join Tristan Thompson's cheating scandal – and revealed the reaction of Khloé Kardashian and his famous family in real time.

When photos and videos of Thompson, 27, approaching another woman just two days before Khloe, 34, welcomed their granddaughter on April 12, the expectant mother was going to nest in Cleveland. At the news announcement, the cameras captured Kim, Kourtney, Kendall and Kylie, who reacted separately on their return to Los Angeles, texting furiously.

"There is a video of Tristan chatting with a girl last night," said 38-year-old Kim. "Khloe will die, she will literally get to work for that.

"I can not even imagine being in Khloe's place, I think it's insane, it's really shocking and obviously heartbreaking," said Kourtney, 39.

"She fired it. He left the house, "revealed Kendall, 23 years old. We try to get her home. "

It turns out that it is Kylie, 21, who has announced the news to her sister.

"Nobody had the courage to tell Khloe because we knew she was going to give birth in a few days," Kylie said. "We did not want to stress it, but we knew it was the right thing to do. So, I'm the one who said Khloe. I did not want to hurt her, but I felt like she should hear from one of us about the Internet. "

Finally, Khloe called Kim in tears, confessing that she wanted to return to Los Angeles but was not sure she could travel so late in her pregnancy.

"You just have to worry about yourself now and stay calm," Kim said.

"I can not stay calm," said Khloe. "Not immediately."

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Kim confessed to feeling "helpless" in the situation as Khloe tried to figure out what she wanted to do.

"She's confused, she does not know what to do and we do not really know what to do, but we want to be there for her," Kim said. "Honestly, I'm shocked. We love Tristan. Honestly, it's nothing we suspected. We thought that she had finally found her prince charming. [her] happy ending. So what F-. That's right, why she? It's really, really bad.

And Kim had heard of other rumors about Thompson's infidelity.

"Honestly, there are so many other stories coming out," she said. "So many friends call me with so many other things. I told him, "What are you going to get out of him? Think about it. You will be worried, nervous and live in precariousness, because if he is not faithful now, he will never change. "

"When something comes out, you're kind of like, well, okay, maybe the video is old or maybe it's a misunderstanding. Because an image does not always tell the whole story, "added Kim. "But then, two more stories come out. It's just crazy. Now, you know it's true. "

But before Khloe could decide on the future of her relationship with Thompson, she went into work. While her mother and sisters made arrangements to get to Cleveland as soon as possible, Khloe asked them to stay polite to Thompson, at least in the delivery room.

"It's like everyone wants me to make a decision in a second and I just want to give birth to that and focus on that, try to take advantage of that and try to do it with him, as crazy as that may appear, "said Khloé. "I want to enjoy it with him. I do not want negativity in the delivery room. I do not want anyone to talk about it, make me feel uncomfortable, or make it uncomfortable. Let's just be normal. Give me a minute. "

Kim agreed to stay cordial – but not without some jokes about how she would welcome him.

"I'm going to watch it and just be like …", she says, mimicking her throat.

"I know how important it is for Khloé that Tristan is here, and I really respect him," Kourtney said. "But it will certainly be embarrassing. It will be difficult to watch or even be in the same room as him. It's as if you meet everyone when you disrespect one of us.

ASSOCIATED VIDEO: Khloé Kardashian publishes an encrypted message that he is "brutally broken"

As PEOPLE had previously pointed out, Khloe finally decided to stay with Thompson and spent the summer with the family rebuilding their relationship in Los Angeles. In recent weeks, however, the couple has had another difficult time.

According to one source, the new mother had a "really difficult time" and "still has a lot of pain and anger".

"Khloé wishes so much that True has a happy family," said the source. "She wants to do her best for her daughter, and for her it means being with Tristan."

But Khloe's mother and sisters "are not happy" about her return to Cleveland and "think she deserves better," the source said. "They definitely do not trust him."

The amazing Kardashian family broadcasts Sundays (9 pm ET) on E!