I am also descended from John Pyper through his son, James Munro Pyper, and James Munro's son, William Wallace Pyper, who is the brother of Alexander Leo Pyper just younger than him. William Wallace Pyper is my grandfather. His oldest daughter, Jessie Isabell Pyper Merrell, is my mother.
In my records, John Pyper married Madeline Gardener on 24 Apr 1846 in Illinois and their son, James Munro Pyper, the oldest of 14 children, was born 14 Jul 1847 in St. Louis, Missouri. Is this the same family as yours? I will be glad to share information with you.