In an exclusive clip from Tuesday's episode of Little People, Big World, the couple — who welcomed their third baby Josiah Luke in April after the filming of the episode — opens up about what it would be like if they were to welcome a child of average height into their family.
"We had a doctor's appointment today, ultrasound, checking on baby. It was kinda fun because I got to show both kids the ultrasound pictures," says Tori as she pulls up the photos on her phone to show son Jackson Kyle, 5, and daughter Lilah Ray, 2.
"All the measurements are average for the weeks, so not a dwarf," says Zach from across the room.
Adds Tori, "I'm getting average height vibes. It's right on track. All the long bones are on track."
In a confessional, the now mom of three says she thinks "it would be fun to have an average height baby."
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"I think if we have an average height it would be different, just like a different experience," adds Zach. "I would imagine having all dwarf siblings just kinda like, 'Hey we're a pack and that's the outside world.' But when you have an average height sibling, [you're like] I wish I was more like my sibling. It changes the dynamic a little bit."
Tori shared similar sentiments about the possibility of having an average height child in a previous episode.
"There's a 50/50 chance this child will have dwarfism," Tori said in an episode earlier this month. "I think it would be kind of interesting just to have one average height kid just to know what that feels like. But I really don't care either way."
Josiah was born with achondroplasia, the most common form of dwarfism, PEOPLE can now confirm. Jackson and Lilah as well as dad Zach were also born with achondroplasia while Tori is of average height.
Tori said her two older kids are super helpful when it comes to their baby brother, who was born three weeks early.
"They are slightly obsessed with him and it's adorable," she said. "They're just both very concerned about where he is, what he is doing. They take turns feeding him the bottle and want to bring him blankies and binkies."
New episodes of Little People, Big World air Tuesdays at 9 p.m. ET on TLC.