In 1949 a person of the same name is enrolled to vote at Mildura, Victoria and until 1968 in New South Wales.
I have been searching for the son Leonard's arrival in Western Australia. Easier to find than searching for Florence as she may be listed as Mrs * SMITH.
This is a possibility and the only one for a Leonard born c1919.
Mr John Thomas Frederick SMITH, 35 years, labourer; Mrs Elizabeth SMITH 30, wife; Leonard 5 years and John Thomas Frederick, 2 years embarked from London on 24 Jan 1924 on the SS BENDIGO contracted to land at Fremantle, Western Australia. Last country of permanent residence, England. Country of Intended permanent residence, Australia.
Of course it may not be them.
Cando