Complex sentence: Alexandra and her four sisters were orphaned early in life and were brought up by their Aunt, Anna Protasov, a chamber-maid of some note and a personal friend of the Empress Catherine II, who was under the care of Madame de Pont.
Split into simpler sentences: Alexandra and her four sisters were orphaned early in life and were brought up by their Aunt, Anna Protasov. Anna was a chamber-maid of some note, and a personal friend of the Empress Catherine II, who was under the care of Madame de Pont.