Just curious to find out---what is emotional retardatiion and how can it be fixed? I cannot find that diagnosis in the DSM... I need some information on this topic. I have 30 and 40 year-old clients who literally act as if and have the emotions of a young teenager.

I think it can be something triggered by an event or a physical condition among other things.
Basically it is simply that your emotions stay at a particular age.

I know kids that started having seizures and ended up with emotional retardation

Also some abused kids can suffer emotional retardation

And the Founder of Gateway rehabilitation
Says that at whatever age somebody starts drugs that is their emotional age as adults.