One is better than two? Jillian Michaels doesn't sugarcoat the realities of having multiple kids when talking to Chelsea Clinton on Just Jillian's Tuesday, February 16, episode, as seen in Us Weekly's exclusive sneak peek.

In the E! series' footage, Michaels, 41, and partner Heidi Rhoades meet up with Clinton, 35, at an event, where the former Biggest Loser trainer warns Clinton that raising two children can bring unexpected challenges. The former First Daughter is currently expecting her second child with husband Marc Mezvinsky but was not pregnant when the episode was filmed.

"Sibling rivalry is a blast, I just want you to know," Michaels, who has two children with Rhoades, tells Clinton. "It's my favorite part."

After Rhoades worries that Michaels is going to scare the former NBC News correspondent, Michaels replies, "It's my duty to warn her ahead of time. One kid is like laughing in the face of parenthood. Two is like a Japanese horror movie."

Watch the video above to see Clinton discuss her parents Bill and Hillary Clinton's excitement about having a second grandchild.

Just Jillian airs on E! on Tuesdays at 10 p.m. EST.

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