Dear Queenie,
After my mother-in-law died my father-in-law gave my wife a lot of her mother’s clothes. Now he expects her to wear something of her dead mother’s whenever he sees us and he gets vexed if she doesn’t.
Queenie, is this strange, or what?—Grossed-out husband
Dear Husband,
If your wife strongly resembles her late mother, it is possible that seeing her dressed in her mother’s clothes is somehow comforting to her bereaved father.
I see no harm in catering to your father-in-law’s preference when you see him in private, providing the clothes are in wearable condition (if they are not they should be disposed of).
However, I would draw the line at your wife wearing these hand-me-downs when you are with your father-in-law in public for fear that if someone recognised them and their source the kind of comment it might draw would be upsetting to him and/or your wife.