Generally speaking, for example, in the hospital whenever a newborn passes away, either before birth, during birth or shortly thereafter, and if the family wants pictures made of the deceased baby before they go home from the hospital, a teddy bear will be placed with the baby as sign of comfort to the baby while the picture(s) are being made. It is only a gesture of love and comfort. Historically speaking, teddy bears are a sign of comfort and this is really the only reason that they are used. I suppose if the family wanted stuffed bunnies, or any other animal, that would completely appropriate...it's just a well known gesture that teddy bears are supposed to bring comfort.
Hope this helps
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