'LPBW' 's Zach and Tori Roloff Enjoy Splashing Around a Lake with Kids Jackson and Lilah: Watch

Zach and Tori Roloff are having fun with their family of five.

In an exclusive preview of an upcoming episode of Little People, Big World, the couple visits a lake with their three children — son Josiah, 6 months, daughter Lilah Ray, 3, and son Jackson, 5.

In a family confessional shot ahead of the fun, Tori marvels that Jackson had become a "swimmer guy" over the summer.

"Yeah, and I can jump anywhere! But not at lakes," the 5-year-old excitedly shares.

When his parents ask him why not lakes, Jackson adorably explains how he like diving in pools.

"Because it's not like something high enough to jump," he says. "Like a pool or something, where I can juuuump!"

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Tori wades into the water with Lilah and Jackson as Zach joins them and he goes in deeper with a floatie-equipped Jackson while Tori watches Lilah splash about.

"When Jackson first started swim lessons, I don't know, he's always been into it, he's just always been hesitant to actually dive in and learn how to swim," says Tori. "[Lilah]'s scary near water because she'll just go."

The toddler then practiced jumping on the couch with mom the way she jumped in the water at the lake.

In another confessional, Jackson jokes that there's something his little sister loves more than her time in the water.

"She just sits in her little chair and eats snacks all day," he shares. "I jump in the water."

Last week, the couple discussed the possibility of putting Lilah in speech therapy to help with her delay. Zach pointed out that because of Tori's background, she may be able to help her out at home.

"Once Jackson starts full days of kindergarten, I think you'll have more time to work with her and do your teaching thing, not to put it all on you," he said to Tori.

"Totally," Tori agreed.

In her confessional, Tori explained, "I have a background in child development. Not that I consider myself a speech pathologist by any means, however, I do have a lot of tools in my back pocket, and I think we can help her a lot at home before we have to step into a specialist's office."