In the collected books of Doraemon, there are a few early stories
featuring Dorami where a bunch of inconsistencies are not explained. 
Nobita seems much more intelligent and competent than normal, and the
Nobi house seems to be designed differently.  If one looks closely at
the artwork it almost seems as if all the human faces have been
redrawn.  This leads me to suspect that the Dorami stories were
actually drawn about a different household (Fujiko F. Fujio did this
before in O-bake Q-Tarou), and that the art was doctored before being
compiled.  Can anyone find out if this was truly the case, and if so,
what were the original characters, when and where were the stories
published, and is it possible to get copies of the original artwork?

Hi, 
I hope I got your question right ^^; you mean Dorami chan ne? 
according to this site http://doraemon.biography.ms/

"Dorami-chan (??????) is a younger sister of Doraemon. She lives in
the 22nd-century Tokyo with Sewashi (???), a Nobita?s grandson. She
likes melon-bun. She seems to be superior to Doraemon. She sometimes
visits Nobita?s by a time machine. Dorami-chan (left side), Sewashi
(right side) http://www.biography.ms/redirect.asp?direction=http://www.ctb.ne.jp/~azx/mission/mission37.jpg"