chicken ain't nothin but a yard bird
Typically used to reassure someone that an event is insignificant and should not be worried about. Also used as a variation of "no big deal".
Friend: "I'm so worried about this test tomorrow..."
Me: "Chicken ain't nothin but a yard bird. No need to worry about it!"
Me: "Chicken ain't nothin but a yard bird. No need to worry about it!"