At least we know Alice was still living at 1901
9 Glasgow St, Partick
George G Davidson 29 b Glasgow. Picture Dealer
Alice Davidson 29 wife b Plymouth
Dorothy Davidson 7 dau b London
George Davidson 3 son b Glasgow
EDIT:
The death of son George W Davidson appears in various newspapers and none mention his mother.
( there is a photo of him printed in the Daily Record dated 11 Jan 1918)
George jnr died at age 20, and would not appear on any electoral rolls prior to his death.
If I have this correct, it seems Dorothy E Davidson lived in Dumbarton Road prior to her marriage but, neither parent is listed in the household.( 1919-1922)
This female disappears from the address at the same time that Dorothy Earle Davidson married.
10 Dumbarton Road was a huge multi occupancy building
There's no way to confirm occupants of individual households but other Davidsons listed were, Madelene R, Catherine S and Annie.