At Victoria and Brandon Hardin's home, the thermostat -- winter or summer -- is usually set at 65 degrees.
They wear winter clothes, including sweatshirts and socks. So does their older son, Cruz, 4.
But, across the living room, the baby of the family, Anthony, 3, sits on the cool wood floor. He's naked from the waist up, exposing his g-tube and trach tube.
He wears a Spider-man bill cap turned backwards, a pair of gray sweatpants and striped socks.
Anthony's body can't regulate its temperature. Overheating could prove dangerous. Even deadly.
As a newborn, Anthony was diagnosed with hereditary sensory and autonomic neuropathy, a rare gene mutation that affects about one in 25,000 people.
The Hardins, who live on Windsor Avenue in Owensboro, lost their daughter, Faith, more than two years ago to complications from the disorder. She was 12.
There are five types of hereditary sensory and autonomic neuropathy. At first, doctors thought Faith had type 5, but genetic testing showed hers was an unknown type.
Anthony, like his sister, has the same type.
"We're still learning," said Victoria Hardin. "His sister was our blueprint."
The disorder affects far more than the ability to regulate body temperature.
Anthony's immune system is compromised, and he has a rare lung disease, pulmonary interstitial glycogenosis. He has suffered from pneumonia at least a dozen times since birth.
His bones are brittle. To make matters worse, he can't feel pain, so his broken bones often go undetected.
For the past few weeks, Anthony's right arm has been set in a cast because he broke a bone in his elbow. He's broken femurs and ribs in the past.
Anthony can't walk. Instead, he scoots on his bottom.
His speech is limited to about five words: yes, no, ma, dad, bye.
"He's never eaten anything by mouth," said Brandon Hardin.
Anthony gets all his nutrition through a g-tube and feeding pump.
His muscles are weak, and he has myriad stomach issues.
However, Anthony smiles constantly, and he's bright, his mom said. His delayed speech is more related to his trach tube than developmental issues.
Brandon and Victoria Hardin met when they were 17 and 16, respectively. She was a cashier at a Kroger in Elizabethtown. He was a bagger at the store.
They fell in love and married a year later.
"We both carry this really rare gene," he said. "It's extremely rare to carry it, let alone meet someone else who carries it."
Cruz also carries the gene but has not been diagnosed with the disorder.
Brandon Hardin is a firefighter with the Owensboro Fire Department. His wife works as Anthony's caregiver and a homemaker.
Anthony's medical condition rules their lives.
At night, he is hooked up to machines that monitor his heart rate and oxygen levels.
"That thing might not beep, or it might beep a thousand times a night," Brandon Hardin said.
So the Hardins rarely -- if ever -- enjoy a full night of undisturbed sleep.
While their home feels comfortable to Anthony, it's frigid to everyone else.
Every time they take him to the store, they carry backpacks filled with emergency medical supplies and other items he may need. And they bring along small, battery-operated fans to cool him if stores or restaurants are too warm.
Even in winter, the Hardin family rides around in their vehicle with the air conditioning on.
This time of year, Anthony doesn't need to bundle up like other children, Victoria Hardin said. His hands and feet cool quicker, so sometimes he wears gloves and shoes, but no shirt.
People gawk and stare, she said. Sometimes, it's worse than that.
The reactions are very hurtful.
"I've gotten people who yell at me," she said. "... You have someone attacking you about something they know nothing about. Our life is already stressful enough."
Some concerned onlookers approach her and ask if Anthony needs a coat. When people are kind, it makes it easier to explain about his medical condition.
Victoria Hardin knows it looks odd to see a small child outside without a coat in winter.
"But this is his normal," she said. "It may not be your normal, but it's his normal."
Renee Beasley Jones, 270-228-2835, firstname.lastname@example.org