Children were in Fallout 3 and the full set of modding tools was available there - so make of that what you will

Also... I'm thinking I should invest in a sock company... they'll have a lot of blown-off socks to replace when the Creation Kit comes out...
In Fallout: New Vegas there was a female child outside the "Atomic Wrangler" in Freeside, advertising booze and prostitution. A male child was advertising for "Mick & Ralph's" saying you could buy items that were illegal elsewhere in the New California Republic.
Seems like if the ERSB or whoever were going to say something about it, they would have stopped them from doing that.
I always thought it was stupid that Oblivion and Morrowind didn't have child models.