Hello Eamon. Yes Dora did have four siblings - Samuel, Frederick, Kathleen and Nellie. They lived in Dublin and show up on the 1911 census. Their mother, Margaret, was my grandmother's sister (mother's side). I have some details of the Ks back to 1837 if you are interested. I can't quite follow the step-sister bit !! Can you tell me how your mother became Dora's s-s ? Regards, Tony.