I think "act like an adult" depends on the content. What was being talked about, what the therapist wants the person to do and then saying those words. I always go by context than by words but some people prefer to go by words than by context.
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Son: Diagnosed w/anxiety and ADHD. Also academic delayed and ASD lv 1.
Daughter: NT, no diagnoses. Possibly OCD. Is very private about herself.