Leah Messer is explaining something difficult to her three girls.

During the Thursday, March 13 episode of Teen Mom: The Next Chapter, Leah learns that her father is facing cancer. As she helps him navigate his medical needs, she decides to wait until she has significant information before sitting her three daughters down to share the news.

“Now that we have more answers, we know what my dad’s treatment plan will look like, and that he told me that he’s committed to his recovery, I’m ready to have that conversation with my daughters,” she explains in a confessional before the sit-down.

Leah goes into the bedroom and tells Aliannah and Aleeah, 15, and Adalynn, 12, “I wanted to get all the answers and figure out what was going on, but about a month ago, they diagnosed grandad with cancer.”

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Leah explains to the girls that their grandfather has kidney cancer and they did testing to see if it had spread to his colon. The testing found there wasn’t any spread.

“They’re going to do an ablation, where they burn off that spot of his kidney, and then he’ll just have a treatment plan after that to keep checking on it to make sure it doesn’t grow back or spread. It was very scary.”

Noting that they’d been estranged from Leah’s dad until recently, Aleeah adds, “He just started coming around and then, now he has cancer.”

“I know this seems scary, but I do want you guys to know that granddad’s okay.”

Ali asks if the illness “could have been from where he didn’t really take care of himself.”

Leah has been honest with her daughters about her father’s struggle with addiction. She explains to them that by abusing prescription painkillers, “he could have masked” pain that would have indicated a problem.

“You guys know the door is open if you have any questions, if you want to see him, whatever that might be,” Leah assures them. “Whatever you might have on your heart, on your mind, just let me know.”

Teen Mom: The Next Chapter airs on Thursdays at 8 p.m. ET on MTV.