Relationship Confusion

I married a widow who had a grown-up daughter. My father, who visited us quite often, fell in love with my stepdaughter and married her. Hence, my father became my son-in-law, and my stepdaughter became my mother. Some months later, my wife gave birth to a son, who became the brother-in-law of my father as well as my uncle. The wife of my father, that is my stepdaughter, also had a son. Thereby, I got a brother and at the same time a grandson. My wife is my grandmother, since she is my mother’s mother. Hence, I am my wife’s husband and at the same time her step-grandson, in other words, I am my own grandfather.