The main reason.
Emily is an emotionally normal child possibly even a overly friendly one whereas Autistic children often present with problems quite quickly autism
Emily is an affectionate and sweet natured child with a character open and trusting enough to be able to endear strangers to her quite quickly. Emily was very clearly an endearing child and good around strangers while as she gets older her behaviour becomes more eccentric and reclusive ocialy, showing “learned” antisocial traits rather than core character traits. While there isn’t a huge number of accounts of Emilys early childhood, the ones that survive most notably from Cowen Bridge talks about her being seen as "a sweet little thing”. Miss Evans, the superintendent of the new school, called Brontë a “darling child” and “little petted Em” and the admissions register referred to her as “quite the pet nursling of the school.” Who doesn’t seem to have had trouble adapting to a different routine and one that was extremely rigid and in almost all respects different to her home life. Nor at this time does she seem to be having any problems interacting with strangers. Autistic children show problems with change and social interactions quite quickly. The negative responses to change and social environments is progressive but variable. It seems that as she gets older she gets less able to or willing to adjust.
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