In 1881 Ann’s brothers are in St Mary’s RC Orphanage, North Hyde, Hounslow, Middx - RG11, Piece 1340, Folio 92, Page 3
George Blake 12
James Blake 11
Henry Blake 11
John Blake 9http://www.childrenshomes.org.uk/SouthallStMary/
One of Ann’s records mentioned Walthamstow School, and the link above says that St Mary’s Orphanage for Girls at Walthamstow was under the same management.
ADDED: Annie's older sister, Mary Blake, married William George Reeves on 19 Sep 1883, as detailed in his WW1 record. In 1891 they have 19 year old John Blake living with them in Chelsea, as mentioned by Jonwarm.