CHONBURI, Thailand >> Thousands of excited fans flocked to a Thai zoo Thursday to celebrate the first birthday of Moo Deng, the adorable baby pygmy hippo that has become a social media sensation.

The Khao Kheow Open Zoo was overrun with Moo Deng fans on the first of four days of activities marking the hippo’s birthday. Children under age 12 can enter the zoo, about a two-hour drive from the capital Bangkok, for free throughout the extravaganza.

Many of Moo Deng’s fans flew miles to see her.

Among them was Molly Swindall, who traveled from New York for the celebrations. She was seen handing a tray of food to a zoo keeper for Moo Deng’s breakfast, which the baby hippo and her mother Jona quickly devoured.

“I just loved her so much and decided, you know what, I have three or four days off of work,” said Swindall, “I can make it work to fly to Thailand. I will only be there for about 30 hours, but that’s enough to go see Moo Deng. And that’s exactly what I did.”

By Thursday afternoon, the number of visitors reached 12,000, zoo director Narongwit Chodchoy said. Despite the noise of visitors calling out for her attention, Moo Deng appeared peaceful as she took a dip in a pond in her enclosure.

Fans photographed the baby hippo with their cameras or cell phones and sang “Happy birthday” as her birthday cake, made of a variety of fruits and vegetables, was placed near the pond.

“Moo Deng is my happy pill, and she’s my energy pill, my curing pill. She’s my vitamin!” said Thea Chavez, who flew in from Houston, Texas.

Jennifer Tang from Malaysia leaned over the enclosure to take pictures. “She makes me happy. Whenever I’m stressed at work I pull up photos of Moo Deng,” Tang said. “So my whole office knows that I’m here .... They let me take a week off.”

The zoo held online auctions to celebrate Moo Deng’s birthday, with photos, footprints and a food container on offer to raise funds for all the animals under their care.

Moo Deng soared to stardom shortly after she was born.