This is part of the Osten-Sacken genealogy:
OSTEN-SAKEN, Comte Family:
Marriage: in St.Petersbourg
Spouse:
TOLSTOI, Alexandra Ilyinitchna Comtesse Osten-Saken nee comtesse
Death : 30 Aug 1841 Optina Pustin
Parents:
Father: TOLSTOI, Ilya Andreievitch Comte
Mother: GORTCHAKOV, Pelageya Nicolaevna Comtesse Ilya TOLSTOI nee princesse
There was a princess from the wife's side of the family, the father of Countess Pelageya was Prince Nikolai Ivanovich Gortchakov.
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And then there is this genealogy of the Diplomat:
Sophia Nicholaievna Balachov
Born 20 April 1885
Married 14 January 1909
Count Nicholas Vladimirovitch von der Osten-Sacken, son of
Count Vladimir Dimitrievitch von der Osten-Sacken and
Princess Alexandra Dimitrievna Ouroussova
Born 17 January 1880
Again it was the female side which held the Princely titles.
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Count Nikolai Vladimirovitch succeeded Count Shouvalov in Berlin.
If you require further information about the Osten-Sacken family then there is another book which you may like to consult:
Les Familles Comtales De L'Ancien Empire De Russie Volume 2 by Jacques Ferrand.
This french language book provides a brief history and family tree of this family.
Hopefully this book will help you with your inquiries.
All the best,
Belochka