honestly, there are hundreds of things they should do to make the game more realistic before they allow you to kill children.
the balance issue, horses not moving like horses, add more dialogue options so you can act like the character you're playing,
making you actually have to sleep, the innkeeper dying from insomnia and exhaustion, making you have to eat,
allowing you to decorate a table in less than a week.
hell, even being able to plow your significant other after some alto wine and skooma....
why is not being able to kill children so important to you? :S