As winifred was registered in Eastbourne, I would have assumed they could be found on the 1901 census. These are some of the birth registrations which I know are correct.
FRENCH, DOROTHY AMY ETHEL TURNER
GRO Reference: 1906 D Quarter in EASTBOURNE Volume 02B Page 59
FRENCH, FLORENCE ROSA ELLEN TURNER
GRO Reference: 1904 D Quarter in EASTBOURNE Volume 02B Page 59
FRENCH, WINIFRED EMILY TURNER
GRO Reference: 1900 D Quarter in EASTBOURNE Volume 02B Page 55
FRENCH, FRANK ARTHUR HENRY TURNER
GRO Reference: 1902 M Quarter in EASTBOURNE Volume 02B Page 70
Doris Alice French
Registration Year 1909
Registration Quarter Jul-Aug-Sep
Registration district Eastbourne
Inferred CountySussex Volume 2b Page68
FRENCH, LILIAN GLADYS IVY TURNER
GRO Reference: 1908 J Quarter in EASTBOURNE Volume 02B Page 71
Beatrice I P French
Mother's Maiden Name Turner
Registration Year 1915
Registration QuarterJan-Feb-Mar
Registration district Eastbourne
Inferred County Sussex Volume 2b Page125
William R T French
Registration DateOct 1917
Registration QuarterOct-Nov-Dec
Registration districtEastbourne
Inferred County East Sussex
Mother's Maiden Name Turner Volume Number 2b Page number105
They could have already had some children before getting married and changed the number of years married to fit (although it doesn't quite fit the oldest child)
Gladys May has mothers name Freeman
I do think the Turner registration is more likely but where was she in 1901