Hume, Fergus: The Opal Serpent, v1, 19 February 2010.
 

Fergus Hume [1859–1932]
The Opal Serpent [1905]

A mystery concerned with murder, inheritance and questions about the legitimacy of the heiress. It is not a good idea to make a will leaving everything to “my daughter” when one has two daughters, only one of whom is the product of lawful wedlock.
(At the time the novel was written, illegitimate children had very few rights in English law.)