I think that maybe Winifred's mother died?
In 1891 and 1901 census returns, Winifred is with her grandfather and his new wife:
1891, reference RG12, Piece 2062, Folio 86, Page 20
36 Harold Street, Hereford
Criddeford, John  Head  M  52  Cabinet Maker  b Totnes, Devon
Criddeford, Susan  Wife  F  45  b Montgomeryshire
Roberts, Winifred  Granddaughter  F  6  b Oswestry
1901, reference RG13, 2481, 79, 11
38 Harold Street, Hereford
Criddeford, John  Head  M  62  Cabinet Maker  b Totnes
Criddeford, Susan  Wife  F  55  b Llanfair, Montgomeryshire
Roberts, Winnefred  Granddaughter  F  16  b Oswestry
In 1881, John Creddeford is a widower.