You often dream that you are a child of 10 years old or a child of1/kloc-0 years old, because you had a particularly painful experience at that age, and these painful emotional experiences were deeply suppressed in your subconscious and constituted painful memories for your mind.
You often dream that you are a child of 10 or a child of 1 1 0. In fact, this is a kind of dissipation of psychological energy, so that you can get rid of the extremely painful subconscious emotions and feel relaxed for a while.