If you happened to pass by the live Nativity scene at the Downingtown United Methodist Church last week, you might have witnessed something of a Christmas miracle:

The donkey. Bobbi Jo, superstar.

Standing in a rough wooden stable and surrounded by children in costume, the 18-year-old miniature jenny expertly played the role of, well, a donkey. In that simple act she sturdily helped celebrate the season, transformed from a thin and sickly beast through the efforts of dedicated University of Pennsylvania veterinarians and a loving Chester County family.

The saga began in spring 2014, when someone rescued an ailing Bobbi Jo at a Pennsylvania livestock auction. She was taken to Penn's New Bolton Center, the Kennett Square hospital known for its treatment of large animals.

"The hard part about donkeys is they're pretty tough, and they can hide their illnesses," said Dr. Michelle Linton.

In this case, though, it was plain the donkey was in trouble. Bobbi Jo was badly underweight, struggling to breathe, not eating, ill with pneumonia. She worked to force air in and out of her lungs, a condition known as the heaves, similar to asthma in humans.

As Linton treated Bobbi Jo with antibiotics, oxygen, and steroids, the donkey's health slowly began to improve. She spent a month in the hospital, undergoing treatment and regaining weight and strength - and charming the staff.

Where some might see simple pack animal, the New Bolton staffers saw a creature that was patient and companionable - with just enough of a stubborn streak to remind you she's a donkey.

"Everyone pretty much fell in love with her," Linton said.

Jennifer Horner Shirk, then a New Bolton nurse, took a special interest in the brown and gray donkey.

"She was really fun to hang out with," Shirk said.

When Bobbi Jo was discharged, she went to live with the Shirk family, moving into their 32-stall barn in Elverson, Chester County, and taking a spot among the horses.

"She's great," said Shirk, who cares for Bobbi Jo with her husband, Enos. Their 15-month-old son, Grayson, likes to walk beside the donkey or try to climb on her back for a ride.

That first winter in Chester County, another New Bolton nurse, Teresa Lewis, mentioned that her miniature horse, Scrappy Doo, was taking part in a live manger scene. The Nativity needed a donkey. Could Bobbi Jo join in?

Shirk connected with the church, and the rest is donkey history. Bobbi Jo has become a staple of the stable.

"She definitely adds," said Dave Moyer, who with his wife, Gwen, organizes the annual one-day Nativity. The donkey's loud "Hee-haw," he said, "really livens the whole thing up."

Which is nice, since donkeys often get a bad rap.

Donkey vs. mule

People don't call them by the correct name - using donkey and mule interchangeably, when actually the terms refer to different animals, according to the American Donkey & Mule Society, publisher of The Brayer magazine. A mule is half donkey, the offspring of a male donkey and female horse.

Donkeys, which can live 30 years or more, get painted as unthinking beasts of burden, useful only for carrying supplies and providing song titles for the Rolling Stones.

In fact, they're highly intelligent, have excellent memories, and, unlike horses, don't easily startle, says Habitat for Horses and Mike's Donkeys, a firm that provides donkeys for children's parties and corporate events.

Their reputation for stubbornness comes from a refined sense of self-preservation. A donkey won't do something it thinks is dangerous.

Domesticated donkeys can be found all over the world. In the United States, at this time of year, they seem as common as reindeer, a fixture in the manger scenes that adorn Christmas cards and fireplace mantels.

Was a donkey there?

But despite their prominent seasonal billing, there's debate over whether a donkey was truly present at the birth of Christ.

The Bible never specifically mentions the Christmas donkey of folklore. No less an authority than Pope Benedict wrote that, contrary to popular belief, no donkeys, oxen, or camels were present at the birth. There's simply no mention of the animals in the Gospels, he noted.

It's more likely that, over time, other ancient descriptions of oxen and donkeys became incorporated into the traditional Christmas story.

Today, a Nativity doesn't seem complete without a donkey.

That's why the Downingtown church was excited to have Bobbi Jo. It wanted to add a camel this year, but the $800 rental fee squelched that. Next year? Maybe chickens, to join the goats, horse, and, of course, Bobbi Jo.

"She seems to really like it," Shirk said. "The kids are really excited to see her."