This is how you do lookups yourself as it is free to search online if anyone has relatives that were born married and died in New South Wales, Australia (within a certain timeframe of course).

NSW Registry of Births, Deaths and Marriages

In the left-hand margin, click on FAMILY HISTORY, then click on SEARCH HISTORICAL INDEXES, then click on SEARCH NOW, click on BIRTH AND DEATH RECORDS, type last name CARTER Given name/s GEORGE and in the year/s to be searched put 1870 to 1890 and click on SEARCH NOW.

As you can see about 39 search results show up. Now with a surname like CARTER in your family tree, it seems to be common and popular like SMITH, JONES, WALKER etc. What you have to do is work backwards from yourself being very careful so as not to waste your $ and research someone else's tree. Purchase the couple's Death Certificates, and purchase their Marriage Certificate. Sometimes marriage cert could have a few more clues, i.e. parents names of the bride and groom, and even witnesses who may have been related.