Option 1 states that the paternal estate was to be divided equally amongst sons. This statement is in line with the Smriti literature, which did prescribe equal division of inheritance among sons.

Option 2 states that women were allowed to retain the gifts they received on the occasion of their marriage. This statement is also correct according to the Smriti literature, as women were allowed to keep the gifts known as Stridhana.

Option 3 correctly identifies the gifts given to women on the occasion of their marriage as Stridhana. This is aligned with the understanding of Smriti literature.

Option 4, however, is not correct. It states that Stridhana was not inherited by the children without the permission of the husband. This is an incorrect statement. According to Smriti literature, Stridhana was indeed inherited by the children of the wife, regardless of the permission of the husband.

In summary, option 4 is the correct answer as it provides inaccurate information regarding the inheritance of Stridhana in Smriti literature.