Green-Eyed Monster (The Berenstain Bears)

The green-eyed monster is an antagonist of the book The Berenstain Bears and the Green-Eyed Monster, as well as the cartoon episode based off of it.

She looks exactly like Sister Bear, except she has green fur and yellow-green eyes. She manipulates Sister into riding Brother's new bicycle, which Sister is too small for. She is not actually real, but a figment of Sister's imagination personifying her envy of Brother's new bike.

One night, she appears to Sister while sister is asleep and convinces Sister to take Brother's bike and ride it. As soon as Sister mounts the bike, the green-eyed monster pushes Sister, sending her off on a bike she cannot control. The bike gets bigger and bigger until it breaks.

In the cartoon, Sister mounts the bike without the green-eyed monster's help, but as her legs are too short, she cannot reach the pedals. Luckily, Brother rescues her in time.