From: Rabbi Moshe Sofer
To: Rabbi Elazar
Rabbi Elazar of Miklós questioned whether the leniency of attributing a kesem to a healed wound extends to wounds on the woman's son or husband, noting that the Rambam, Ra'avad, and Ramban appear to limit this to the woman herself. The Chasam Sofer upholds the Shulchan Aruch's ruling that attribution to son and husband includes healed wounds, marshaling the Rashba, Semag, Sefer HaTerumah, Mordechai, Semak, and Rabbeinu Yerucham in support, and harmonizing the ambiguous Rishonim with this majority view based on the Gemara's own logic and the Rabbinic status of kesamim.
Source: Shu"t Chasam Sofer YD §186