Why everyone is so sad about this dead fish

It might be easy to roll your eyes at the thought of mourning a fish, but for one aquarium the loss of Granddad had nearly everyone in tears.

Granddad the lungfish has been at Chicago's Shedd Aquarium since 1933 and staffers think he was in his mid-90's.

This would make him the longest-living fish in a zoo or aquarium setting in the world, outliving several generations of his caregivers.

Granddad was put down after he stopped eating and showed signs of organ failure.

Staffers are treating his passing like a death in the family because he felt like family.

Over 104 million people have seen him throughout the years, according to the aquarium's president.

Granddad was 4 feet long and weighed about 25 pounds.

He had a pretty easy life, getting pats on his back while eating worms and leafy greens.

Lungfish are among the few fish that can breathe air. They are native to Australia and are a protected species there.

According to the aquarium, they can live to be more than 100 years old.

With a life-span that long, no wonder Granddad has so many people sad to see him go.

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