Certainly not a Prince or a Don, because he was born illegitimate. He
can style the family name. But if the church acknowledged him maybe he
can style Don. Not sure if his branch were granted Princes of the Holy
Roman Empire, that would be the only way to style prince for younger
siblings born legitimate. http://www.angelfire.com/realm/gotha/gotha/ruspoli.html
1d) Alessandro Pr Ruspoli Pr di Cerveteri (Rome 9 Dec 1924-Rome 11 Jan
2005); m.1st Rome 8 Dec 1947 Nob.Francesca dei Baroni Blanc (Rome 27
Jun 1920-Milan 27 Feb 1962); m.2d Vignanello 5 May 1964 (div) Nancy de
Girard de Charbonnières (b.Pouillon 18 Apr 1939); m.3d Rome 20 Nov
1993 Theresa Patricia Genest
1e) Francesco Pr Ruspoli, Pr di Cerveteri, b.Rome 31 Mar 1967; m.Beth
O'Rourke
2e) [by Debra Berger] Tao, b.Bangkok 7 Nov 1975; m.in Virginia 7 Jun
2003 Olivia Jane Cockburn (b.10 Mar 1983)
3e) [by Debra Berger] Bartolomeo, b.Rome 6 Oct 1978; m.2005 Aileen
Getty (b.1975)
4e) Mathilda Mélusine, b.Paris 25 Jul 1994
5e) Théodore Alexandre, b.Paris 30 Apr 1997