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Transclude of The-psyche-of-babiesMy reasoning for babies being UDUF is that the ego is not developed when you’re born, so it must be only the unconscious and possibly superego that are present (UD).
The second reason is that being born is the first traumatic event of a person’s life - you’re ripped from the safety, comfort, and order of the womb and thrust into a bright, loud, chaotic world that you don’t understand. How could that not make you UF, at least for a time?
In my mind, the process of developing consciousness for a baby is becoming SDSF, and this is also why child abuse and other extenuating circumstances fuck children up so badly. It interferes with this process of becoming SDSF and developing the ego, keeping them in UDUF and causing the ego to be underdeveloped. It’s like a tree trying to grow in a hostile environment - it will grow in stunted and twisted.