I can't find 1871 on FS to see if Louis is a son or grandson.
RG10 Piece 3225 Folio 53 Page 26
Civil Parish: Great Bowden
Registration District: Market Harborough
Sub-RD: Market Harborough
No of Schedule: 170
Address: Main St
Joseph Cort Head Mar 45 Ag Lab...
Vic. Marriage 1881 CORT Willis Joseph (b. ) - LAING Susan Cath Sinclair (b. ) Vic. #1274
Is the date 15 March ?
SA Death 1941 CORT Susan Catherine Sinclair d. 25 Dec 1941 rel Willis Joseph CORT [DH] Dist 1 Book 645 p.83
The Advertiser (Adelaide, SA) - Fri 26 Dec 1941 p.8