Good work there, Sue.
I noticed earlier when I read Ruth's Probate record, that she had been resident in Taihape (a smallish North Island town).
Have also found Ethel Isabella NEAL was listed registered to vote on the 1911 Waimarino roll.
That tends to suggest that she'd probably been in NZ earlier than 1911 ?? She was working at Taihape as a waitress at that time.
Added: Same register 1911 also under her married name and living at Hihitahi. Ruth Olive NEAL first appears on Waimarino (supplementary) roll in 1914 living at Huia Street. Being on supplementary roll may mean she had only just arrived in the district.
Added: Or, meant she had only just attained the voting age of 21 (I see she was born 1893).
* Do you think the girls may have gone to live with relatives in New Zealand ??
Unfortunately with these trans-Tasman "voyages" lasting only a few days, and with no requirement for Australian citizens to carry travel documentation, it was simply just a case of jumping aboard at one end and off at the other. Often passenger details were simply shown on the manifest as "XXX number in steerage" (no names recorded).
You could try searching the NZ Passenger lists at FamilySearch (although many are for immigrants).
https://www.familysearch.org/search/collection/location/1927083 ~ Lu
Added: Ethel Isabella NEAL married Ernest Edward MANNING on
13 September 1911.
Edits to add further information/ afterthoughts.