 The Gemara replied that teaches that though a son was born after a miscarriage (and thus did not "open the womb" and is not regarded as a firstborn son for purposes of "sanctification to the Lord" and "redemption from the priest" in ) he is nonetheless regarded as the firstborn son for purposes of inheritance.thus implies that only the son for whom the father's heart grieves is included in the law, but a miscarriage, for which the father's heart does not grieve, is excluded.