I just want to add that when he says, "You gotta let go when they get that old, you gotta let 'em go" that holding onto for instance, a grudge for years and years until it has become old will do nothing but grow and hurt you. It grows to consume a person's life and stops them from living life to the fullest, so you have to "let them go" when you've simply held onto something so unhealthy for so long.
I just want to add that when he says, "You gotta let go when they get that old, you gotta let 'em go" that holding onto for instance, a grudge for years and years until it has become old will do nothing but grow and hurt you. It grows to consume a person's life and stops them from living life to the fullest, so you have to "let them go" when you've simply held onto something so unhealthy for so long.