I think you should definitely talk to T about it. I worry if T may not be prepared, to just let inner child have the entire session, I don't want her to somehow get emotionally hurt if T is not quite "with it" yet. But it does sound incredibly important that the inner child have some connecting and safe time with T. Maybe talk with him about it first getting there. Maybe because of feeling anxious and worrisome about it, instead of having to tolerate an entire session of her being out, what if starting with half a session? Or could she have this session, and you have an extra this week?

You are not alone. Though I know it feels very scary right now, we're here with you, and most important, T is too.