Friendship is like a flower. If cultivated well, it can produce more happy flowers. However, once willfulness or misfortune fundamentally destroys friendship, this flower that blooms in the heart can wither immediately.
Things went wrong because of my brother's willfulness.
People often say that willfulness is freedom, but willfulness is only irrational freedom. The choice and self-determination of human nature is not out of the rationality of will, but out of accidental motivation and its dependence on the perceptual external world.