Down Syndrome and Self-Talk
It's that inclination to rant or work something out that leads me to what I now know is called "self-talk." I also work through questions and answers when I'm working on a tricky problem, be it in reality or fiction, and there's always a lot of self-talk going on in the car with my steering wheel. You don't even want to know what I say to my computer.
Marcus used to ask who I was talking to, now he doesn't bother.
So, when Marcus followed suit with his own self-talk, I wasn't alarmed. And I certainly never thought of it as part of Down syndrome.