Generally world wide violence against children is a big nono. It will get your game blacklisted by a lot of people and cause controversy. Small baby versions of creatures like minecraft is ok because they really are not associated with children. Shooting a anatomically correct child zombie would turn a lot of people off from the game, especially those who have children themselves.
a quick google reveals there has been some dismay over that. I've never heard of days gone before now and I have to wonder if the child zombies didnt stop some of the advertising and word of mouth that usually happens.Days gone integrated child zombies in a great way. Newts. agile wall climbers that hang out on roof tops and only attack if you attack first or invade their territory. It really does add to the game and I don't think that game was banned anywhere.