the family was only recognised in march 1879 and he was created count in 1893 . He was given the castle of Sommariva Bosco near Cuneo which is still in the family. I think his mother was installed at Villa Pietraia near Florence ( which is quite isolated) and bought the Sommariva estate . The decendants are listed in Addingtons "Royal House of Stuart". His sister married two Marchese Spinola ( brothers) and thirdly Paolo de Simone who committed suicide in 1906. Her mother died at her Palace near Pisa
seems unlikely they would have been very friendly with their Royal half siblings, the family mausoleum in Turin is styled like the Pantheon in Rome.
The name of the castle is Sommariva PERNO, the Counts of Mirafiori lived also at Fontanafredda (near Alba, Piemonte, Italy) unitl 1920