it’s always worth a try to contact the civil registration, but most of the records for Elsene/Ixelles and Brussels are online (on Familysearch or on the Belgian State Archives)
https://familysearch.org/search/collection/list#page=1&countryId=1927071click on : Brabant Civil Registration 1582-1914
click on : Browse through 6.411.594 images
then click on the town / commune of your choice
(date dd/mm/yy)
https://familysearch.org/pal:/MM9.3.1/TH-1-18261-89379-25?cc=1482191&wc=STV3-3TG:966896201,1489058001cert n° 209
Marriage 20/02/1892 11 am Brussels
bridegroom : Richard Caudwell, 27/07/1866 Egnanton (Egmanton ?), Nottingham, England, servant, there domiciled, now residing at Brussels avenue d’Auderghem n° 34, before Brussels at Etterbeek
parents Richard Caudwell
Helene Caudwell (formerly Lacey, see marriage annexes image 757)
bride Amelie Cuypers, born 22/05/1874 Brussels, ironer, living at Impasse Saint-Roche n° 12
parents Pierre Cuypers, deceased (04/10/1885 Brussels see marriage annexes image 768)
Elisabeth Brousté, without profession, present an consenting
witnesses Joseph Hanssens, 29 years old, commissioner
Jean Georges Cuypers, 26 years old, tanner, brother of the bride
Martin Cuypers, 22 years old, cigar maker, brother of the bride
Joseph Puttemans, 47 years old, (brewers man/or - servant/or - lad ?)
all living at Brussels
marriage publication : 07/02/18992 at Brussels and Etterbeek
marriage annexes (suporting marriage documents) image 755 up to and including image 768
https://familysearch.org/pal:/MM9.3.1/TH-1971-31730-8915-76?cc=1482191&wc=ST24-JWG:966896201,1493434501birth cert n° 313
https://familysearch.org/pal:/MM9.3.1/TH-1-18255-56045-41?cc=1482191&wc=STV9-N3D:966886201,1489063601 Richard Caudwell born 05/04/1896 2 pm at rue de Florence n° 20, Ixelles / Elsene
parents Richard Caudwell, 29 years old, born Egnanton (Egmanton ?), Nottingham, England, coachman
Amelie Cuypers, 22 years old, born Brussels
domicile Egnanton (Egmanton ?), residing rue de Florence n° 20 Ixelles
birth cert n°322
https://familysearch.org/pal:/MM9.3.1/TH-1-18360-23113-93?cc=1482191&wc=STVN-RM9:966886201,1489961301Georges Caudwell born 05/04/1902 4 am, at rue Keyenveld n° 26, Ixelles/Elsene
parents Richard Caudwell, coachman, 35 years old, born Egnanton (Egmanton ?), Nottingham, coachman
Amelie Cuypers, 28 years old, born Brussels, without profession
domicile Egnanton (Egmanton ?), residing rue Keyenveld n° 26, Ixelles