She said to his other wife.
I'm not the general's wife
But my childhood sweetheart's sister
It's a pity that this sister is destined to never get married in this life!
He has two wives.
He said to one of them: "Husband and wife are one body, sharing weal and woe. I entrust all the affairs of the family to you."
But he said to the other: "You are the wife who is being married by the emperor, and I am the matchmaker. How can you be your sister?"