Energetically - this is all based on my own observations as an energy reader/healer during my own pregnancies. The baby's soul starts to mesh at conception...however it is a slow process and it's the energetic structure of the mother's aura & body that allows the soul to mesh more fully over the whole period of the pregnancy (this is why we can't gestate any mammals to independent life without the incarnational vehicle of a mother's body). I noticed my babies' guides stepping in at a very definite point in the pregnancy (can't remember exactly when but I think it was the 2nd trimester) which I think means the soul had connected firmly to this lifetime's incarnation at that point. Ideally the child's aura remains connected to it's mother's for a number of years after birth, fully detaching only around 7 years old, which is why kids react so much more strongly to their mothers' emotional state than anyone else in the family. Birth itself is more of a physical adjustment than an energetic one, particularly because the mother typically continues to hold the child within the energy of her heart chakra. There are also chakras in the nipples, so breastfeeding also continues to provide energetic nourishment as well as physical (it's the hidden ingredient in breastmilk that gives breastfed babies that "glow"). The energetic attachment continues until the child is somewhere around 7 years old (although some more mature spirits detach earlier) and the detachment takes place gradually, unmeshing a layer of the aura/chakra system at a time. In some traumatic circumstances the aura is disconnected early but this results in ongoing energetic (and emotional) trauma in the child's life. I have also observed that it is possible to have a (very) early miscarriage which results from sperm meeting egg and starting to divide without a soul attempting incarnation at that point.
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