The Talmud proposes an alternative interpretation of the mishna.

Rav Yehuda said that this is what the mishna is saying in the expression “all mitzvot of a son with regard to his father”: With regard to all mitzvot of a son that are incumbent upon his father to perform for his son, men, i.e., fathers, are obligated in them and women, mothers, are exempt. In other words, the obligations that the Torah imposes on a father to perform on behalf of his son are not incumbent upon his mother.