Tosefta sobre Ketubot 8:16

These are those (sic!, the word "inheritors" is not in the Ehrfurt manuscript) who come with her permission [whom the inheritors can force to take an oath, even if they exempt her from doing so; see Mishnah Ketubot 8:5): Anyone to whom she sold [the property in question] or gave as a gift. If he wrote for her [in the ketubah]: "I will have no vow or oath upon you", the inheritors are not able to cause her to swear on things that were used after the death of her husband [that she didn't use them and therefore owes no money]. When does this apply? When she went from her husband's grave to her father's house. But, if she went from her husband's grave to her father-in-law's house, even if he wrote for her "I will have no vow or oath upon you", the inheritors are able to make her swear about property she used after her husband's death.