Deuteronomy 21:15 If a man has two wives, הָאחַת the one loved and the other hated and they both bear him children and if the firstborn son is from the woman who is hated: 16 Then when it comes time for him to pass his inheritance to את־ his sons את which he has may not begiven to the firstborn …
Ki Tetze (when you go) out to war
Deuteronomy 21:15 If a man has two wives, הָאחַת the one loved and the other hated and they both bear him children and if the firstborn son is from the woman who is hated: 16 Then when it comes time for him to pass his inheritance to את־ his sons את which he has may not begiven to the firstborn …