I am married to Ingrid Mennes. Her father's grandfather was Pieter Mennes (1882-1911). His older brother was Jan Mennes (1881) who came to Kalamazoo Michigan in 1907 (John Mennes) and started a business in photo equipment I believe. He married the Dutch girl Hiltje (Helen) Datema (1878). She died 1948. They had possibly 5 or 6 children.
In 1951 John Mennes went back to The Netherlands / Groningen to visit family (also the only son of his brother Pieter) and married Johanna Achterhof, daughter of Siert Achterhof and Annegien Dijkstra.
Siert Achterhof was born Ulrum, 24-09-1868, Son of Johannes Achterhof and Lena Huizinga and died (81) Ulrum, 24-12-1949.
Johanna Achterhof (1901-1972) was the oldest daughter of John's older halfsister Annegien Dijkstra. John's and Pieter's mother was Emke Mennes and the father of her 5 ! children was NN, but I found out that it was Albert Dijkstra (1850-1907).
When John and his second wife Johanna went back to Kalamazoo in 1952 her younger brother Albert (1904) went along. I don't know about his life in Kalamazoo.
So, my wife is related to Johanna (and Albert) Achterhof through Johanna Achterhof and John Mennes.
John Mennes died (98) Vicksburg Kalamazoo 1979.
Roosendaal, The Netherlands