Question: When did Albrecht Of Saxe-Weissenfels's mother die?
Answer: 11 December 1669

He was the fifth and youngest son of August, Duke of Saxe-Weissenfels, and his first wife, Anna Maria of Mecklenburg-Schwerin. Anna Maria of Mecklenburg-Schwerin (1 July 1627, in Schwerin – 11 December 1669, in Halle) was a German noblewoman, a member of the House of Mecklenburg and by marriage Duchess of Saxe-Weissenfels. She was the fourth child and second daughter of Adolf Frederick I, Duke of Mecklenburg-Schwerin by his first wife Anna Maria, daughter of Enno III, Count of Ostfriesland