All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
It is permissible for your son to wear your slippers even during the days of your monthly periods. The slippers differ from the clothes which are stained by the bleeding of menses. The items of a menstruating woman as well as her slippers are pure; for more benefit, please refer to Fatwa 93768.