I have discovered the grave locations of Arthur John Martine, Patricia Monica Lake & Gertrude Mary Martine's at Rookwood cemetery. 

You can search here.

I then found John William Martine was married to Gertrude Mary Bernasconi in 1918 at Randwick.

I then found Gertrude Mary Bernasconi born 4857/1889(b) Leichhardt, New South Wales, Australia

Parents John A Bernasconi & Sarah L A Newton. Married 1887  Sydney.

Siblings Marie L 1891 & Catherine M 1892.