Four children of Joannes (Jean) Serpentier and Sybilla Thijssens can be found:
30.04.1814 Helena Catharina Serpentier (Charpentier) Oud-Vroenhoven, †22.07.1889 Tongeren (BE). She married Paulus Smits (Smets) 06.04.1839 in Oud-Vroenhoven and had 6 children between 1840 and 1854, moved to Tongeren.
xx.xx.1818 Petrus Serpentier †28.02.1824 Oud-Vroenhoven/Canne
14.10.1820 Caroline Serpentier* Canne †13.04.1869 Oud-Vroenhoven
25.08.1825 Gerardus Serpentier Canne
Caroline* married Joannes Willems 25.07.1845 in Glons (BE).
They had 5 children:
09.02.1847 Marcellus Hubertus Willems Oud-Vroenhoven †27.09.1913 Oud-Vroenhoven
12.01.1850 Isabella Hubertina Willems Oud-Vroenhoven †12.02.1858 Oud-Vroenhoven
xx.xx.1852 Elisabeth Willems Oud-Vroenhoven †06.08.1875 Oud-Vroenhoven
14.03.1857 Johannes Willem Willems Oud-Vroenhoven †13.09.1939 Maastricht
15.01.1864 Gertrudis Willems Oud-Vroenhoven †26.12.1940 Heer (Limburg NL)
Confusing it is that Caroline was registered with the name Caroline at birth and at her marriage, and that on the birth-registrations of her children and her death, the name Helena is used.
a little diagram here:

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