Hi....l found Alice age 3 born Box Wiltshire living with Parents and siblings in 1891....here hoping from the names Stella may recognise some of the info. I worked with the Salisbury connection and found that even though Alice seems to marry Herbert Dyer in London in 1909(maybe working as servant) she comes back to Salisbury to marry George Billen. The only other Alice A Fletcher born similar birth year is born in Lancs and residing in Lancs in 1891 and another 1889 birth is Alice Mary from Swindon. The only other two are 1881 and 1883 births so little too early?
1891 Corsham Wilts
Frank Fletcher Head M 30 Platelayer GWR Hemmington Somerset
Emma Fletcher Wife M 30 Wellington Somerset
Frank Fletcher son 4 Box Wiltshire
Alice Fletcher dau 3 '' ''
George Fletcher dau 1 '' ''
and then found the same family in the 1901 and found all births consistant with Chippenham (registration District) for all children in this family
1901 Priory Road Chippenham RG13 /1918
Frank Fletcher Head M 39 Railway Worker Somerset
Emma Fletcher Wife M 39 ''
Frank Fletcher son 15 Box
Alice Fletcher dau 13 ''
George Fletcher son 11 ''
William Fletcher son 9 ''
Lena Fletcher dau 7 ''
John Henry son 5 ''
Annie Arene? dau 3 ''
Walter Charles Fletcher son 1 ''
and here they all are....
Frank Fletcher Chippenham Sep Q 1886 5a 59
Alice Fletcher Chippenham A/M/J 1888 5a 61
George Fletcher Chippenham Mar Q 1890 5a 69
William Fletcher Chippenham J/F/M 1892 5a 74
Lena Fletcher Chippenham J/F/M 1894 5a 65
John Henry Fletcher Chippenham J/A/S 1895 5a 69
Annie Irene Fletcher Chippenham J/A/S 1897 5a 63
Walter Charles Fletcher Chippenham Sep 1899 5a 69
if this is familiar to Stella(and i hope it is the right family)
I also have marriage details if you do not have already. As you already looked under Fletcher surname for birth of Stella and didnt find one maybe the 2 sisters married and Stella was born in one of those names ? It is a real longshot but you never know, otherwise it could be just a straight case of an adoption, which is horrible for Stella as you said earlier because all word of mouth info has now been lost
Let me know how you get on with this info and if l can help some more l will
very best wishes cheryle.f