She is married to Johannes George Kroonenburg.
They got married on May 11, 1836 at Amsterdam , she was 24 years old.Source 2
Johanna Margaretha Fontijn | ||||||||||||||||||
1836 | ||||||||||||||||||
Johannes George Kroonenburg |
https://www.familysearch.org/ark:/61903/3:1:939D-9X4S-F?cid=partner-a02j000000GMFDcAAP&i=184&cc=2020117
https://www.myheritage.nl/research/collection-10562/nederland-huwelijksregister-burgerlijke-stand-1811-1940?itemId=7879709-&indId=externalindividual-f1858b99645b4f5dcd3e44493fdd9665&mrid=482261a2d2d212ac5a93ec8388578c73&action=showRecord&recordTitle=Johannes+George+Kroonenburg+%26+Johanna+Margaretha+Fontijn