Dorothea Sibylle of Brandenburg

She was a daughter of John George, Elector of Brandenburg by his third wife, Elisabeth of Anhalt-Zerbst.

She was also known as Duchess Dorothea Sibylla of Liegnitz and Brieg, and was born as the Margravine of Brandenburg.

Born in Berlin, Dorothea Sibylle was the fourth and youngest daughter of her parents.

After her father died in 1598, she grew up in her mother's estate, Crossen (in present-day Poland).

On 12 December 1610, Dorothea Sibylle married her maternal cousin, Duke John Christian of Brieg.