Eldest Sister-in-Law Zara slandered Song Chengshuang as infertile, demanding she be expelled. Song Chengshuang made an agreement: whoever gives birth to the first grandson first, their child will be the rightful heir. Song Chengshuang conceived twins, uncovered misdeeds, exposed them. The eldest sister-in-law reaped what she sowed and left. Song Chengshuang obtained property, and the family lived a happy life.