to answer your questions first you need to know what ......my..... location and .....my ..... own treatment providers called co consciousness....

examples....

knowing of the alters existence
being aware of what is going on inside the body with self and alters while at the same time knowing what is going on outside the body and self.
sharing memories, information between alters and each other and the one that they reside with in.
no amnesia or time loss during the time the alter is in control
being awake and aware of ones own thoughts, emotions, perceptions as ones own while at the same time knowing the alters own thoughts, emotions, perceptions as their own.
not hallucinating or delusional or otherwise out of touch with whats real and what isnt.

The alters that I was co conscious with...I knew they existed, perceived them to be totally separate from me, they had their own sense of agency and I had my own sense of agency..I could hear their voices, know how they were feeling, knew their feelings/ emotions were theirs and mine was mine. I knew not only what they were thinking and doing but also knew what was happening both inside and outside my body...

could I selectively supress my alters.....no I could not selectively supress any of my alters. my dissociative type alters were dissociation related meaning any time I was triggered into having my dissociative symptoms/ problems which ever alter who's sense of agency was to handle that trigger took control and handled it/ took care of that problem.

example if thunderstorms caused me to dissociate then the alter who's sense of agency was thunderstorms that alter took control, got out of the storm, home into dry clothing, can calmed down. once the triggering event was taken care of I was back in control.

(Just a bit of info about DID if a person doesnt have alters that take control they are not diagnosed with having DID, just how psychiatrists in america diagnose the disorder you can read more about what DID is and what is required to happen in order to be diagnosed with this in america by reading the DSM 5 at your local library, this is the diagnosing book treatment providers use along with testing processes)

no my DID was not something I could choose to have and choose when what alter comes out when. it was solely dependent on when I had my dissociation symptoms. I did have some alters who's sense of agency was to take care of those triggering times when I was home alone, hiding, or bathroom situations. but it wasnt a thing where I could say ok Im going to go to the bathroom and climb into the tub with my blankie and then switch into being the alter sleepy..... it was like taking off my clothing scared and frightened me so much that I felt numb, spaced out and my bathroom alter took control took off the clothing, took a bath then got dressed again, once everything that I could not handle was done and I was no longer scared, frightened, dissociated I was back in control again....

DID isnt something I .....chose to be......., its something that happened to me. its called a dissociative disorder in me because in order for my alters to be in control I had to be dissociated.

co consciousness here where I am does not mean I got to choose. it just means I was aware of what was happening and so on.

also something to consider here if someones alters only were in control during private times how would they get diagnosed with having these alters... being able to tell a treatment provider that one has alters is only a small part of the diagnosis process here. one of the things about this is that it has to affect all aspects of a persons life (you can read more about this in the DSM5 requirements for having DID in america just the way treatment providers do things here in america now)

whats the difference between alters and the child with in....

here in my location the child with in is a therapy approach where it is believed that everyone has feelings, reactions, emotions thoughts and behaviors that are age appropriate and older or younger....

its like someone says something you dont like and you fly into a rage like a child would when their parent says no. or times when you feel so happy you feel like you did on christmas day when you were a child. you dont literally change into alters, its just those times when you naturally behave or feel like a child.

the therapy for this is imagining you are sitting in a room with that feeling like a child, imagine what would that feeling, thought or behavior look like, can you imagine picking up, holding, calming down that child you used to be.

some people find great comfort in doing this visualization... example last night I was angry at something that happened to my neighbor. I was so angry I wanted to throw things, I wanted to scream and yell. I went into my bedroom, sat on my bed and purposely wrapped up in my favorite blanket then closed my eyes, took a few deep breaths and thought ok this feels like the time when I was a child and something similar happened to me. I was this age and looked like this..... now Im going to talk to that child I used to be.... hello little amanda, I know you are scared and angry what can I do to help you feel better, then I think about what I needed back then when I was that scared angry child. I needed someone to tell me everything would be ok, that I would be back with my family soon and that I was safe now... again talking to my imagined visualization of the child I used to be... Amanda I know its scarey to be away from home and that you are afraid the people that hurt you will find you, you are safe now, everything is going to be ok, mommy and daddy and the casworker are going to make sure those people never hurt you again and that they cant find you here. can I hold you, give you a hug... then I imagine the child I used to be reaching up to me and my holding her. still in this visualization I tell myself that what happened was years ago, Im no longer that helpless child scared and alone. I am a grown adult what can I do now about todays situation...

then I opened my eyes, took a few deep breaths then I left the bedroom to call my neighbor and offer her my shoulder, a hot meal and what ever other help I could offer her instead of acting out like the child I used to be.

I hope this has answered your questions... mind you this is only going on what is with in me and according to my own location and own treatment providers...

for answers as they pertain to you, your locations definitions and treatment providers you will have to contact a mental health treatment provider in your off computer location. they will tell you whats what where you are.