Kid Sister was a great doll - she came with bib overalls and was supposed to be like your little sister. She had a pretty realistic face and hair, that you could style yourself and she was available as a blonde, brunette etc.
There was a version of Kid Sister for boys as well called My Buddy.
With an appearance not too dissimilar to a Cabbage Patch Doll, Kid Sister was originally produced by Hasbro in 1985 and measured around 20-inches tall, so she was pretty large. In 1990 the toy was taken over by Playskool and her face and clothes changed slightly.