All that can presently (October 2023) be gleaned about Rosie Fitzgerald from sheet music covers and by Internet searching is that she was presumably an Australian child vocalist who has been featured on 2 works published between 1906 and 1907.
She was cast as Alice in a pantomime Alice in Wonderland (lyrics: Saville Clark music: Walter Slaughter). It was performed by juvenile actors at Her Majesty's Theatre, Sydney on 24 December, 1906.
Her portrait on the left is taken from The Kids From the Alley (1906) music by Frederick Wynne-Jones, and published by J. Albert & Son, Sydney, New South Wales, Australia.
Surfers are welcome to contribute any further information about this performer.