That’s not what they meant by putting an “ass” in a diaper.

A pampered UK donkey named Kye acts just like a dog after being rescued and raised alongside a family’s pet pooches.

“He’s certainly a character,” owner John Nuttall, 64, told Newsflare of his mongrel-imitating mule, who reportedly responds to a whistle, fetches balls and even follows his human wherever he goes.

Nuttall, who owns a donkey-ride business near Lincolnshire in eastern England, said the 3-month-old ass first started down the road to dog-dom after his mother rejected him and became violent. This prompted the mule boss and his partner, Gražina Pervenis, 40, to hand-rear the Eey-orphan themselves.

“The previous year, the mother gave birth to a foal that she wouldn’t take to, and it ended up dying,” explained Nuttall. “We thought there was something medically wrong with the foal, so we tried again this year, but then she rejected this one, too.”

The donkey boss added, “I was lucky enough to be there when she was attacking him, and I managed to get him inside.”

They initially tried feeding Kye milk from his abusive mother, but his health began to deteriorate, so the pair took the abandoned creature home and weaned him on formula.

For the next six weeks, the adoptive parents shared custody of Kye in their separate homes, where he was constantly around their pet pooches.

“There was nothing I could really put him with that was his size, and I didn’t want him to get hit by other donkeys,” explained Nuttall, who owns 70 of the ungulates. “I kept him in the house, and then he used to go in the garden with the dogs, so he grew up with me and the dogs, really.”

Like a mule version of “The Jungle Book,” the donkey soon began to exhibit some canine characteristics.

“I would whistle to the dogs, and so he comes to a whistle,” exclaimed Kye’s incredulous owner. “Now, if I get in my van to go out, he’ll see it going and chase after the van.”

He added that the Fido-identifying foal “even started playing with a ball and everything, and now, I can go for a walk down the road, and he’ll follow me like a dog.”

As Kye is not potty-trained, Nuttall went to the pet shop and bought him “big dog nappies” so he wouldn’t poop all over the floor.

Hilarious footage shows the diminutive donkey clomping around the house in his plus-size diaper.

Nuttall ultimately that hopes one day that Kye will dump his doggie ways and join his fellow mules in giving tourists rides on the beach, Newsflare reported.

But for now, he’s just grateful that the petite pooch impersonator, who moved into the donkey enclosure three weeks ago, is getting healthier every day.

“My main concern was to keep him alive,” said Nuttall.