The mother-in-law, from the very birth of her beloved grandson, nags the daughter-in-law that she has worked him up. 28 years later, the daughter-in-law decided to prove that she had never cheated on her husband, and also passed a DNA test with her son. According to the mother, either both tests will be positive, and the mother-in-law will calm down, or both DNA tests will be negative, and her son was replaced in the maternity hospital.