On a cold January day in 2017, nearly two months before due date, Nile hippopotamus Bibi gave her keepers at the Cincinnati Zoo and Botanical Garden a big surprise: a tiny newborn hippo, no bigger than a football. The first premature hippo born and raised in captivity, baby Fiona was an underdog from the start: she couldn't nurse, she couldn't stay hydrated, and she wasn't thriving. But the staff at the zoo knew they could save her. They had to study the makeup of hippo milk for the first time ever and reach out to medical colleagues, including a team at the local children's hospital with superior vein-finding skills, to ensure that Fiona would begin to gain weight and become healthy. She soon became an internet sensation, her pictures and videos garnering thousands and thousands of likes and fans on Instagram and Facebook. Now a Fiona appearance at the Zoo mimics a Beatles concert. But what made this little hippo such a big hit all over the world?