The Prodigal Son turned from his wild living back to a restored relationship with his father. His older brother, however, was self-righteous, judgmental, selfish, and didn't have a proper relationship with his Father. The story Jesus told was cut short, with the obvious application being to the Pharisees, and by extension any of us, who think they have a good relationship with God but don't.
Watch: https://youtu.be/SLv82MPeH_c