Anal Retentive - Origin

I believe the term refers to an infant who retains his/her excrement for fear of soiling his/her diaper.

From memories of Psych 101 circa 1967:

Parents who are very strict with their children when it comes to toilet training and who disapprove of soiling will produce an anal retentive offspring. This offspring person will be very neat and concerned about order and cleanliness. Any psych students out there to give more detail?

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