Hogle Zoo keepers said Pogo the giraffe first showed symptoms that she was sick on Sunday afternoon, and by Monday she was gone, along with her unborn calf.

She was 17. The unborn male calf was in “perfect condition," but at 48 pounds he was too small to survive, the zoo said in a Facebook post.

It’s unclear why she died, although a necropsy found Pogo’s intestines were “abnormal,” the zoo said, adding, “it’s not clear why it all happened so fast.”

Pogo made headlines in September 2018 when she gave birth to Georgetta, who was 150 pounds at birth and over 5 feet tall, zoo spokeswoman Erica Hansen said.

If you’ve ever fed a giraffe at the zoo in the summer, the zoo’s post said, it was most likely Pogo.

“Pogo was a wonderful giraffe, a great herd member and quite curious," keeper Melissa Farr said in the post. "She was interested in things, even if she didn’t want to participate. She was a wonderful companion to the other giraffes and a perfect mother to her calves.”

On Sunday, when keepers noticed Pogo appeared uncomfortable, they initially worried something was wrong with the unborn calf and Pogo was preparing for an early delivery or stillbirth.

Through Monday, the zoo said, Pogo didn’t seem better.

“While veterinarians were in the barn to administer medications, Pogo lied down and we weren’t able to get her up or revive her,” according to the post.

The zoo said further testing will be done to determine why she died, but said results could take weeks. According to the zoo’s website, the average lifespan of giraffes is 15 years.

Pogo is survived at the zoo by her daughter, Georgetta; the baby’s father, 16-year-old Riley; and 2-year-old herd member Minka.

Hansen said that unlike chimpanzees or elephants, giraffes don’t typically mourn deaths of herd members. She added that the zoo typically allows animals to inspect the body of a deceased enclosure-mate to come to terms with the loss.

Georgetta also seems to be OK, Hansen said, adding that Georgetta and Minka had spent much of the day playing.