Zach and Tori Roloff‘s son and daughter were both born with achondroplasia (the most common form of dwarfism), but the Little People, Big World stars say that they don’t want dwarfism to be their children’s sole identity.
“It’s obviously a part of them, but we don’t want dwarfism to define our children,” Zach says in the latest issue of PEOPLE, on newsstands Friday.
Before the TLC star, 29, and Tori, 28, (who is average height) welcomed their son Jackson, 2, and daughter Lilah, 4 months, the couple knew their child would have a 50 percent chance of inheriting achondroplasia.
“That wasn’t a concern to us,” says Zach. “Sure, there was a chance our kids could have dwarfism, and there was also a chance that none of our kids would have dwarfism. Whatever we got is what we were going to love and roll with.”
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Monique Serra Zach and Tori Roloff with son Jackson and daughter Lilah
Zach knows his children will share a unique bond. “I think it will bring them closer than your typical brother-sister relationship,” he says.
As they get older, “Jackson will be setting the precedent at school,” Zach predicts. “He’ll be punching through those barriers. When it’s time for Lilah to start going, the school will already have an awareness of what the needs are. He’ll be blazing that trail for her.”
In the meantime, the couple want to teach Jackson and Lilah how to handle any difficulties they may face in the future. “You do have to just push [Jackson] a little bit more,” Zach says of his toddler.
“When he’s running with the other kids, he’s a little slower than the rest. I just say, ‘Keep going, dude.’ The height difference is just going to get bigger as he gets older, and the other kids are going to get faster. But I try to not baby him. I want to build that resilience and mental toughness in him early so he’s able to overcome later challenges, especially when he’s at school and doesn’t have Mom and Dad around.”
For the pair, raising a family has become their greatest joy. “It’s just given me such purpose,” says Tori. “I pray that my kids grow up to be good people. If I do that, then my job on earth is done.”
Little People, Big World airs Tuesdays at 9 p.m. on TLC.
For more on Zach and Tori Roloff, pick up the latest issue of PEOPLE, on newsstands Friday.