We see Walter and Elizabeth living at 49 Yelverton Road, Coventry, Warwickshire, at the time of the 1939 Register.
James W (Walter) Knibbs 25 Sep 1906 Radial Driller Motor Wheel Manufacture Married
Elizabeth Knibbs 17 Nov 1905 Core Maker Foundry Work Married

We see Elizabeth with her family in 1911, living at 67 Silverdale Street, Openshaw, Lancashire:
Charles Ganson Head Mar 30 Labourer Lancashire
Elizabeth Ganson Wife Mar (5 years) 26 Charing Lancashire
Elizabeth Ganson Daur 5 Droylsden Lancashire
Edna Janson Daur 4 Droylsden Lancashire
James Janson Son 3 Droylsden Lancashire
Alice Ganson Daur 11 months Droylsden Lancashire
Alfred Ganson Brother 11 School Droylsden Lancashire
Elizabeth Hadfield Cousin 19 UnM Spinner Droylsden Lancashire

The census shows that Charles and Elizabeth had 4 children before 1911, but two had died. James and Alice had been crossed out in red ink so I suspect it was those two who died.
__________

Elizabeth married Walter in 1930.
__________


From the Coventry Evening Telegraph - 02 April 1962:

Woman's 40 Years At Sterling Metals
MRS.ELIZABETH KNIBBS of 48, Yelverton Road, Coventry, is believed to be the first woman to complete 40 years' service with Sterling Metals Ltd. She received a gold watch from the firm at the annual distribution of long service awards at Sterrnet Hall. Nuneaton, on Saturday afternoon. Workmates in the iron core shop also marked her achievement by presenting her with a bouquet of flowers.

The watch was presented to her by Mr. E. Player.