Hi, the chances are that she may have gone into foster care, especially if the mother returned to the previous address. Do you have your mother's birth file? Did you trace the Thearle family tree in isle of wight or find a death certificate for them, which might have Edna having signed it as the legal child. Do you know anything about the Thearles? (I found a PH Thearle in the phone books). they would be the first place to start maybe. If Edna was adopted before 1927 there wont be a birth file. Let me know any other info - my email is email@example.com
thanks J. Do you know if Edna changed her name to Thearle?