Re the 'birthday' card, perhaps you are not used to bad writing (like mine!) but I read the 'unusual' name as 'Webster', and sure enough in the 1901 census there is an 11 year old Amy Webster living at 53 Cato Street with her builder father George (47), mother Anne (49) sisters Frances (21), Anne (19), Bertha (19) and Emma (13).
There isn't a no.51, so the address must be 51 & 53 Cato Street - George's business perhaps, as he is listed as an 'Employer'.
Checking further, both Anne and Bertha are registered 3rd quarter 1881 in Aston, vol 6d page 339, so they must be twins!