‘Helen inspired us all.’ Second-oldest gorilla in the world dies at Louisville Zoo.

Helen, a 64-year-old western lowland gorilla who became known as the “Grand Dame” died Friday at the Louisville Zoo.

The zoo said she was the second-oldest gorilla in the world and the oldest in North America, according to the zoo.

“Helen had been on quality of life watch and was in natural age decline for several months. Zoo caregivers made the difficult decision to euthanize Helen today,” the zoo announced in a news release Friday.

Helen was born in the wild in the west African nation of Cameroon in about 1958, and the zoo celebrated her birthday in January each year.

She had lived at the Louisville Zoo since 2002, when she came there from the Lincoln Park Zoo.

“Helen inspired us all with her longevity,” Kristen Lukas, chair of the Gorilla Species Survival Plan with the Association of Zoos and Aquariums, said in the news release. “She touched the lives of many people over the years, including those who cared for her and those who just spent time visiting her at the zoo. She was an independent spirit as well as being an integral member of her gorilla family, and her legacy lives on.”

Helen was a mother of three, and two of her descendants, great-grandson Bengati and great-great-granddaughter Kindi, also live at the Louisville Zoo.

The zoo posted a video on Facebook in which Helen’s caregivers remembered her “bold personality” and how she’d purr when she was happy and bark at her keepers to let them know when she wasn’t. They said she also was known for singing.

“She always had a crowd gathered around her because she loved to have the attention of the babies, and she loved to make herself known and express herself with the people around her,” Curator Jill Katka said in the video.

The zoo said the typical life expectancy for a female gorilla in a zoo is about 39 years. The oldest gorilla in the world is Fatou, who is 65 and lives at Zoo Berlin in Germany.

Though she previously had suffered only from arthritis and periodontal disease, the zoo said “Helen recently developed increasing instability and tremors. This put her at greater risk of falling which impacted her day-to-day welfare.”

“Letting go of a special gorilla like Helen is very hard, but it is often the last, best thing we can do for our animals,” zoo Director Dan Maloney said in the release. “Helen’s exceptional longevity is not only a testament to her personal constitution, but also to the outstanding care provided by her keeper team and the animal health care staff over these past 20 years. Helen was one of our most beloved ambassadors. Her fascination with human babies delighted families for decades. I know our friends and members will share in her loss and miss her greatly.”