Honey, a 29-year-old Asiatic black bear, died on Friday night.

The Cheyenne Mountain Zoo (CMZ) had to say goodbye to one of its longest residents this past weekend. On Friday night, 29-year-old Honey—a female Asiatic black bear—began showing signs of "sudden illness and "pain," say officials at CMZ. Following an exam, they then made the difficult decision to euthanize her after "serious age-related conditions" were discovered.

Honey and her sister, Beezler, came to the zoo when they were just shy of a year and a half old, living at CMZ for nearly 28 years.

At the time of her passing, Honey was the oldest-known Asiatic black bear living in human care—tied with her sister, of course.

"I had walked by their exhibit for years, but until I met and started working with them a couple of years ago, I never realized how cool they were," said Courtney Rogers, lead animal keeper for the sisters. "Even though they were sisters and lived together all their lives, Honey and Beezler had very different personalities. We often described Honey as a ‘sweet old lady,’ but she could also be super assertive at times."

Honey and Beezler had a close relationship and would typically choose to spend time together. In fact, keepers said even though they had the option of separate sleeping dens, the sisters would be found sleeping near each other the next morning.

"Honey was the more laid-back of the two," said Erika Furnes, another animal keeper for the bears. "She was a slow eater, which I could relate to, since I’m the slowest eater in my family. Beezler would often get to treats first, but when Honey really wanted something, she would stand up to Beezler and protect her portion with her paws. Sometimes, they would alternate stealing lettuce from each other – Beezler would swipe some into her pile, but then Honey would swipe it back. And they’d continue, back and forth."

In light of her sister's passing, keepers are keeping an extra-close eye on Beezler.

According to CMZ, Beezler spent time with Honey on her final day. Beezler's behavior over the weekend seemed normal, say the keepers, who will continue to give her extra attention in the coming days and weeks, to help make the transition easier for her.

Did you ever visit Honey and Beezler at the Cheyenne Mountain Zoo? Have any photos/videos to share? Let us know your thoughts in the comments below.