I don't know if you have this:
Baptism St James Gunnersbury
20th Aug 1889 Eva Lilian, parents David & Mary Matilda Hummel, of 2 St Mary's grove Chiswick, Timber Merchant.
There's also a letter of administration granted 25 April 1890 to his father, value £2134 15s 10d
I can't find any evidence of her being back in England as a Hummel.
Have you followed her mother's line forward to see if she turns up with them as a Warren?
Or is she with other members of the Hummel family in Sweden. Is she with her grandmothers family, you don't mention her surname.
Dawn