It was a tough few months for the Cincinnati Zoo's beloved behemoth: Henry the Hippo had lost his appetite, only to regain it and lose it again; fought off a serious infection; and his kidneys appeared to be shutting down.

The 36-year-old hippo — father to Fiona, whose underweight birth made her famous on social media — died today.

Veterinarians and care staff had been trying to bring him back to health, but he continued to slide in recent weeks.

"We're doing everything we can to keep him comfortable," the zoo said in a recent blog post.

According to the zoo, the median life expectancy for a Nile hippo is 35. He came to Cincinnati from Dickerson Park Zoo in Springfield, Missouri.

His declining condition came near the tail-end of a pretty joyous year for hippo staff: They nurtured Fiona into childhood after she born six weeks early and half a calf's normal birth weight. The entire hippo bloat -- Henry, Fiona and mother Bibi -- were all reunited just a few months ago.