Emotionally immature people lack certain emotional and social skills and have trouble
relating to other adults. Some behaviors can be a signal that you’re dealing with an emotionally immature person:
Impulsive behavior. Children are often impulsive. They speak out of turn or touch things that they shouldn’t touch. They say things without thinking about how they’ll affect other people. Over time, people learn not to do those things. Emotionally immature adults haven’t learned to curb their impulses. They act in unpredictable or antisocial ways.
Demanding attention. Young children get bored when people don’t pay attention to them. They’ll do things to draw the focus back to themselves, even if that means acting out in negative ways. Emotionally immature adults often do the same. They might not act out in negative ways, but they may inject themselves into conversations or crack inappropriate jokes to get everyone’s attention.
Name-calling and bullying. In general, adults don’t resort to schoolyard tactics when they relate to other adults. You seldom see two adults calling each other mean names. Someone who behaves like a mean kid in school is not using mature emotional tactics. Instead, they are relying on childlike displays of temper.