Shirley, You will need to purchase the birth certificate for Lydia from the Registry Office in Melbourne. They are about $17.50 and are quite detailed. The name of the mother should be on the indexes with the reference no. Think that the Victorian indexes are on line but you have to pay. Alternatively they are available free at LDS family history libraries, most major city libraries and Genealogy Societies. If you are just a beginner, then read a book on how to trace your family history, get advice from the LDS libraries or the Genealogy Soc. Most people are quite willing to help.