I am not sure this holds. Many of your thoughts are formed as you speak, there is even evidence that talking to yourself in third-person helps you stay more calmer and objective.
https://aeon.co/ideas/why-speaking-to-yourself-in-the-third-...
https://aeon.co/ideas/why-speaking-to-yourself-in-the-third-...
Talking to yourself in third-person means having switched into thinking of yourself as some third party which can itself affect subsequent thoughts/talking, so this doesn't contradict what the parent says.
I am talking about the usual thoughts you have that are unprompted.
I feel like the article is not disagreeing with me on that necessarily.
There are also experiments that support that idea: