I can't order the birth certificate right now, but maybe she could be Diana Sarah Tapper's daughter?
Name: Mother's Maiden Surname:
TAPPER, SARAH IDA FLORENCE SMITH
GRO Reference: 1863 D Quarter in HACKNEY Volume 01B Page 350
If she is Diana's daughter, Diana was already pregnant when she married Henry Tapper in June 1864.
I couldn't find any other references to Sarah Ida Florence Tapper and Ernest Henry John Tapper.
