hi again
found this on the 1861 cencus if you look at the son david .............same christianname,same age and same place of birth.then look at mothers and fathers age.possibly mother remarried??? and david was from earlier marriage? might be worth seeing if you can find a marriage for this couple.i know its a long shot but you never know

Charlotte Marshall abt 1798 Brill, Warwickshire, England Mother Newent Gloucestershire
David Marshall abt 1859 Ledbury, Herefordshire, England Son Newent Gloucestershire
George Marshall abt 1860 Brierly Hill, Staffordshire, England Son Newent Gloucestershire
John Marshall abt 1829 Cleeve Prior, Gloucestershire, England Head Newent Gloucestershire
John Marshall abt 1864 Droitwich Son Newent Gloucestershire
Letcher Marshall abt 1836 Bredon, Gloucestershire, England Wife Newent Gloucestershire
regards
alli