Hi and welcome to Rootschat
I see they married in 1852 in Shipston on Stour
Have you checked freebmd for marriages for their children and then looked for them on subsequent censuses?
www.freebmd.org.uk for example - there is an 1894 marriage for a Giles Manderson in Stratford on Avon to either Elizabeth Cox or Elizabeth Edkins
1901 census for Warwickshire shows he must have married Elizabeth Cox. As the marriage was only 1894 - unless Giles had a previous marriage, Emma & James are not his children but are shown as Manders
All children b Warwickshire
Giles Manders 46 agric. labourer b Shipston on Stour (died 1922 - see freebmd)
Elizabeth 44 b West Bromwich
Joseph Cox 15 b Binton
Emma S 14 b Binton - see freebmd - Emma Selina M Cox
James H 11 b Grafton
Ellen 8 b Grafton
Gwendoline A 5 b Grafton
Mira M 3 b Grafton
RG13 Piece 2944 Folio 101 Page 4.
Isaac was unmarried in 1901 and still living with widowed mother Selina so you would need to search the 1911 census for him to see if he was married by then - I can't see a marriage on freebmd