The birth has
WHISLER ALICE ROBERT CLARK FLETCHER LILLIE FREMANTLE
WHISLER ALICE 11M ROBERT CLARK FLETCHER ALICE FREMANTLE
1899 WHISLER MARY ANN ROBERT CLARK URRY LILLIE
1901 WHISLER MINNIE ROBERT CLARK URRY LILLIE
1903 WHISLER LILLIE ROBERT CLARK CROCKETT LILY LOUISA
1905 WHISTER DOROTHY ROBERT CLARK CROCKETT LILLIE
If you check WA BDM and search for the various surnames used by Lillie you will find other children with different men/man and some of the children above listed also.
URRY FRANCIS Male CROCKETT LILLIE Female PERTH
Chances are there is no marriage for FLETCHER and it was a married Lillie who was the mother.