Child

Children are the young inhabitants of the wastes. In Fallout 3, a child is a human character under the age of 16.

Differences between the games
Children are killable in the first two Fallout games. If you kill them you get the Child Killer Reputation.

Children in Fallout 3 and Fallout New Vegas cannot be killed. Bethesda faced a similar problem when making The Elder Scrolls IV: Oblivion, as they considered adding children to make the game more realistic, but this was controversial -- if the children could be killed, Bethesda could be accused of making a child murder simulation. Bethesda's response was to simply make the characters invincible. This once again raised issues, because the tactic would undermine the whole point of children being there, which was making the game more realistic. Eventually Bethesda scrapped the idea for The Elder Scrolls IV: Oblivion, but in Fallout 3 they have gone the other way, allowing children for realism, but making them invincible. The only child that can be killed in Fallout 3 is in Tranquility Lane, which is you.

Fallout 3 Notable Children

 * Arthur Maxson
 * Maggie
 * Harden Simms
 * C.J. Young
 * James Hargrave
 * Bryan Wilks
 * Rachael
 * Ralph
 * Flower
 * Biwwy
 * Bumble
 * Eclair
 * Joseph
 * Knick Knack
 * Knock Knock
 * Lucy
 * MacCready
 * Penny
 * Princess
 * Sammy
 * Squirrel
 * Zip

Fallout 3

 * Harden Simms and Maggie, two child-inhabitants of Megaton, disappear from the game if you choose to blow up Megaton. Nothing in-game shows or confirms that they are dead. Should you leave Megaton after arming the bomb and return before detonating it, neither of the kids are present anywhere.
 * Arthur Maxson, the only child-inhabitant of the Citadel, will disappear from the game should you choose to blow up the Citadel in the final quest of Broken Steel.
 * Sticky, killable oddity of Little Lamplight, is not a child.
 * Timmy Neusbaum of Tranquility Lane is removed when you are given the task to slaughter the residents, or when you turn on the Chinese invasion program. A unique Garden Gnome called "Timmy the Gnome" is placed on the Neusbaum doorstep, indicating that Timmy's Tranquility avatar has been altered.
 * Children cannot be targeted in VATS.
 * Mister Sandman perk cannot be used on children (with the exception of some bugged game versions).

Fallout New Vegas

 * The kids running around in Freeside have the same voice, regardless of gender.