The 31-year-old Little People, Big World star shared a series of photos on Instagram Thursday documenting his and Jackson's recent "road trip adventure" to California.
"Jackson and I recently had an epic road trip adventure and decided to finally post about it," he began in the caption alongside the sweet pics. "We road tripped down to Grass Valley CA for a quick visit with my grandparents, Jackson's great grandparents."
He continued, "Drove down on Friday, came back on Sunday and slept in the car both ways. Not many 4 year olds can rally like that but Jackson's not like many 4 year olds.. this trip proved that again. We made an epic detour coming back and found a cool active fire tower with Fireman Bob reporting the fires on Mt Shasta and in the area."
"I love road trips and small towns, takes me back to what seems like simpler times," Zach concluded.
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His wife Tori commented below the post, "Best dad ever."
"Sounds like a great time," Zach's mom Amy Roloff added. "Awesome memories."
On the current season of LPBW, Zach and Tori, who also share 1½-year-old daughter Lilah, have been grappling with the prospect of Jackson needing surgery on his legs in the near future. (Both Jackson and Lilah were both born with achondroplasia — the most common form of dwarfism — like their father.)
"The doctor says his legs are an issue but it's not an emergency," Zach said earlier this season. "It's kind of deep down what I think I expected, it's all about deciding when, where and what the best surgery is. It's the beginning, I think, of a long journey."
"Hearing that Jackson's going to need surgery, that was heavy and that's going to be scary when that day is here," Tori, 30, added.