The first thing of interest is two sisters, Anna Maria Moll (1821-1894) and Antje Moll (1810-1899) marrying two brothers, Gerrit van Ingen (1816-1886) and Jan Rijnaud van Ingen (1813-1871). Not shown in this chart are three children of Ran Rijnaud and Antje, Gerrit (1835-1910), Johanna Christina (1837-1901), and Cornelia (1841-1878). Of the three, only Johanna Christina van Ingen married, producing eleven children. Of these, five died in infancy. Four others are known to have died unmarried. There are no further signs of the remaining two (Cornelia van Ingen, born 1870, and Antoon van Ingen, born 1876, both in Arnhem) in the Dutch civil records. However, there are indications that the latter served in the military in the Dutch East Indies.
In the next generation, we see the first case of cousins marrying. Gijsbertus Moll (1846-1929) married his first cousin Anna Maria van Ingen (1849-1911). One of their five children, Evert Moll (born 1884) married his first cousin Cornelia Clasina Moll (1883-1923), daughter of Gijsbert's brother Gerrit Moll (1843-1907). Her sister Cornelia Moll (1880-1943) married her first cousin Evert Moll (born 1881), son of another of Gijsbert's brothers, Evert Moll (1845-1928).
In the last generation, we find another married couple, Gerrit van Ingen (born 1882) and Woutertje van Kampen (born 1888). These two were second cousins.
Of course, the tangles don't end here. Among the descendants of Gerrit van Ingen and Anna Maria Moll, there are additional tangles, not shown in the chart. Consider two of their grandchildren children, Anna Maria van Ingen (1895-1978) and Gerrit van Ingen (1891-1972). Anna Maria married Aart van Maanen (1890-1973). Gerrit married Neeltje van den Brandhof (1890-1977). Aart and Neeltje were first cousins, grandchildren of Arend van den Brandhof and Johanna van Donkelaar. Among the ancestors of other in-laws, there are tantalizing hints of the possibility of other interrelationships. But that will have to wait for further research.