You might also consider to contact a local association with interests in local history. Perhaps some volunteer knows about the family(history) or is able to look up the birth records (older than 100 years) in the city hall (because not sure they are quickly soon put on microfilm once the 100 year limit is reached). But Walcourt still should (or very likely) have the original records.
Here is the address of the association (library):
Walcourt Cercle d’histoire de l’entité de Walcourt Monsieur Ernest Crepez Rue de la Montagne, 3 B-5650 Walcourt Belgium
Phone : 071/65.59.58 ============================== I believe Mr. Ernest Crepez is also on Facebook (apparently he lives in Yves-Gomezée nearby) and on the white pages (phone) www.infobel.com [name:crepez city:walcourt]
Just give it a try. In the worst case you can get a no or no answer.