This article is from the Care of Orphaned Kittens FAQ, posted to rec.pets.cats newsgroup. Maintained by Sharon Talbert with numerous contributions by others.
Toddlers should be encouraged to play and extend themselves, but they must be contained in a safe, small room. Do not give small kittens the run of your home or apartment, particularly if they are in the process of being socialized! Start newborns with the denning box, then at about three weeks allow them out of the box to explore a small, kitten-proofed room that is warm and secure. A spare bedroom is a good living space, a bathroom is fine, as long as the lid is left down on the toilet and floor isn't too cold (newspaper is a good insulator if that is the case). Provide a den (the carrier or nesting box) as safe haven and sleeping place.