Dreams dictionary: Adult
Dreams dictionary: Interpretation 1
In the event that you are a kid or young person and dream that you are a grown-up, then it suggests that you should be more develop about some circumstance. Maybe you make them grow up that you have to do. On the other hand, the fantasy might strengthen your awareness of other's expectations.
Dreams dictionary: Interpretation 1
If you are a child or teenager and dream that you are an adult, then it implies that you need to be more mature about some situation. Perhaps you have some growing up that you need to do. Alternatively, the dream may be reinforcing your sense of responsibility.