I rather wonder if she caused or suffered a split from her family? All BMD entries appear to confirm the true family name as "Holmes".
The 1911 census entry shows her as "Louie Holmes", as if her employer was perfectly well aware of her proper name, but then scratches out the final "s".
She presumably joined the QMAAC as "Holme, but there is no surviving service record (as others have found).
More interestingly, her Medal Index Card in the name of Holmes, LOUIE, gives "Enlisted 15/10/1917, Discharged 08/09/1919 (Medically Unfit)." No medal entitlement is shown, but it does mention List WAAC/344. This is a Silver War badge Roll.
Going to this roll we have: WAAC/344 Worker 4100 Holmes LOUIE, [dates as above], Badge Number B338743, Medically Unfit - Served Overseas: YES.
Now what do we make of a zero campaign medal entitlement against the statement that she served overseas?
