I am not following this.

The way I see it my children have multiple grandparents including two sets of step grandparents. Their biological father remarried and his new wife's parents became my children's step-grandparents. I don't bother with the 'step', they are my children's grandparents. Similarly, when I remarried my new in-laws became step-grandparents too. When it comes to my step-son, my parents became his step-granparents too. Adopting has nothing to do with this. So I don't get your point. And what has this to do with bed-wetting?