My intention now is to reach out to the Evans family. Perhaps they might have some photographs of Nellie/Lily when she was young.
Use the search box here
https://recordsearch.naa.gov.au/Search as a guest and enter Leonard Trellisian Evans.
This will give you his digitised RAAF service record of Lily and John Evans' son, Len. It is very large, out of chronological order and contains blank pages etc. Plod through

.
It holds the names of his 2 children. Daughter born 1943 Son born 1944
This I believe is the death notice of the son. 2021. Age not given so cannot be be certain
https://www.mytributes.com.au/notice/death-notices/evans-lionel-patrick/5763350/ This is likely the daughter with a matching birth and death year.
YEOMANS Colleen Frances
10 JUNE 2012
Death age 69
Herald Sun (Melbourne) 12JUN2012
Leonard died
EVANS Leonard Trellisian
19 SEP 2014
Funeral
Age 93
Late of Glengara Village, formerly of Wamberal and Melbourne.
Central Coast Express Advocate
And SMH
17 SEP 2014
Mona died
EVANS Mona (Audrey)
23 FEB 2008
aged 87
At Gosford Hospital, late of Glengara Village, formerly of Caringbah and Wamberal
Central Coast Express Advocate
27 FEB 2008
Sue