At this point, so many silly complaints have been lodged over absolutely nothing that I can't tell if this is a legitimate concern or satire.
Well the complaint is either that you can kill kids in this game, or that you can not kill all kids in this game. Honestly this should be out of the question totally, but the OP is correct that it is at least a double standard, especially when your game is otherwise trying to be very inclusive.
It is also not consistent with the current lore, as in SoD you at least can have a goblin follower, who is true neutral and a rather gentle soul, too. It is said that she is this way, because of her maturity, so she might be an outlier, however does mean that Goblins are not absolute evil. This does not matter either, as the morals of the story are a reflection of today's morals. And in today's morals killing of infants or kids is universally condemned, especially deliberate. Going against that code of conduct is so rare, that the need of representation through implementation of it is inherently worthless.