Daniel the duck flew from Wisconsin to North Carolina in the US. Photo / Mark Eddig, Twitter
Daniel the Duck won over the internet this week, but he's not the only farmyard animal to take to the skies.
He may not be your typical support animal, but he's definitely one of the sweetest.
Meet Daniel Turducken Stinkerbutt, an emotional support animal for a nervous flyer, who found internet fame when he accompanied his owner on two flights across the United States this week, reports Fox News.
Mark Essig was on the same flight as Daniel from Charlotte to Asheville, in North Carolina.
"My seatmate, CLT->AVL, is this handsome duck named Daniel," Mr Essig tweeted.
"His gentle quacking eases the sadness of leaving #SFA16."
Daniel belongs to Carla Fitzgerald, who developed post-traumatic stress disorder after she was hit by a texting driver in 2013. She has had him since he was a duckling and is officially certified as an emotional support pet, meaning he can go wherever she goes.
"First of all, he's got a calming effect," Ms Fitzgerald told the Citizen-Times.
"Second of all, if I start heading toward the PTSD, he senses it right away and he's able to calm me down. If I'm standing he'll try to climb on my legs, and if I'm sitting he will face me. He'll climb my chest, and that's my cue for me to lie down. And then he sits on my chest until it passes. Then once it passes, we go about our day."
Daniel is far from being the only farmyard animal to take to the skies.
The United States Congress passed an Act in 1986 allowing service animals to fly in the passenger cabin, however, the passenger requires documentation from a mental health professional and the animal can't be left to roam around the cabin.
Passengers have brought turkeys, pigs, tortoises, lizards, a miniature horse, and even a kangaroo on board as support animals.
Earlier this year, Captain Tom Bunn — a former commercial pilot who now helps people manage their fear of flying — told Fox News it's all too easy to get a therapist to write a note.
"Any therapist can sign off on any kind of animal," he said.
"Science has proven that when dogs look at you with total devotion, it produces oxytocin, a hormone that shuts down the fear mechanism. The turkey, I don't think so.
"When I saw that turkey on Twitter, I thought here we go . . . Some people are going to very annoyed that they paid several hundred dollars to fly with a turkey."
Some animals, such as well-trained service dogs, are typically well received by other passengers, however more unusual species can cause problems on board.
"It really is getting to the point where it's become uncomfortable for other passengers," Laura Glading, national president of the Association of Professional Flight Attendants, told NBC.
"And flight attendants are getting put in the middle. We've had over 50 documented cases. I would say dozens of instances where planes have returned to the gate. Passengers have unruly pets, dogs snapping at other passengers."