young.. special various reading called Sevir (App-34) reads "their laying nest": i.e. before all the eggs are laid.
Related Commentaries of Deuteronomy 22:6
Deuteronomy 22:6
6 If a bird's nest chance to be before thee in the way in any tree, or on the ground, whether they be young ones, or eggs, and the dam sitting upon the young, or upon the eggs, thou shalt not take the dam with the young: