He is married to Maria de Blocq van Kuffelaer.
They got married in the year 1779, he was 28 years old.
Child(ren):
https://www.genealogieonline.nl/nazaten-karel-de-grote/I88876.php
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Nederland's Adelsboek, 1905
p. 545
https://archive.org/details/nederlandsadelsb282unse/page/n377/mode/2up
Willem (!), not Louis.
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Willem (Louis ?) Quarles van Ufford | ||||||||||||||||||||||||||||||||||||||
1779 | ||||||||||||||||||||||||||||||||||||||
Maria de Blocq van Kuffelaer |
The data shown has no sources.