Hi Robert,
I've had a look through the 1841 Cranbrook census, but couldn't spot Caroline. I didn't actually see any Needham families, so it could be that they had already moved away. Is Caroline still there in 1851, or any later census that you've found her on, or have you details of her parents or siblings that she might be with. I can have another look for her if you've any more clues to help locate her.
xx Carol