The phrase "silly story" refers to a fictional tale that is funny, ridiculous, or not meant to be taken seriously. It often includes exaggerated or humorous elements that make people laugh or entertain them. Full definition
I'm not just telling silly stories in front of people that want a laugh. (sciencemag.org)
Just a bunch of silly stories made up by people that were so scared of the world around them they came up with a god to explain what they could not explain. (religion.blogs.cnn.com)
Across his life, he's written silly stories about talking birds and cats, teenage angst - ridden poetry and is currently working on his first novel. (inspiringinterns.com)