Big Mama, I agree with all the posts above, but would like to add that "inner child" can also feel like another self separate from your main adult self. It depends on how dissociative you are. I've just recently admitted to T that my inner child has a transference with her, both negative and positive. I think inner child can be just a childlike place at times for all people, but a more separate dissociation problem for others. DID indicates that the child inside is more definite than a playful part of oneself.

If there was a lot of trauma in early childhood, and then a very strong need to survive, and have the defense of omnipotent denial, that inner child becomes deeply repressed, despised, and embarrassing. When there has been early emotional neglect and abuse, there is a lot that has been repressed, and it's exerting a lot of pressure on your present adult life.

The more I can discuss and recall of my inner child (alter) and the more transference I can trust with the therapist, the more integration and strength I gain. But I'm still very much in the scary suspenseful , stage of it all.
Maybe you could do a web search about DID and see about where you fit in. I'm so glad I finally started working on this and trusting it to be in therapy. I hope you keep on with yours, too.