Complex sentence: She was the daughter of the Russian Prince Alexei Dolgorukov and niece to Prince Vasily Lukich Dolgorukov and grew up with her brother Ivan in Warsaw in the house of her grandfather Gregory Fjodorovitj.
Split into simpler sentences: She was the daughter of the Russian Prince Alexei Dolgorukov and niece to Prince Vasily Lukich Dolgorukov. She grew up with her brother Ivan in Warsaw in the house of her grandfather Gregory Fjodorovitj.