I just wanted to chime in again about 'child-like' and 'childish'. The 'youthfulness' is part of the make-up of an ENFP and no matter how old physically we get, we'll always hang onto the idealism and optimism and true *joy* and excitement over things that is considered "child-like". It's really hard to truly jade an ENFP.
Does anyone remember Calvin and Hobbes and the Frosted Chocolate Sugar Bombs story line where he sends away for the beanie (that thinks will make him fly?) See how 'jaded' he got when he had to wait 4-6 agonizing weeks for it to arrive (that's freakin ETERNITY in child years) and how he said it ruined him? That's how jaded ENFPs get. We may act like we're done with something or someone or crushed and Will Never Believe Again, but 9.5/10 chances, we're not.
We want to believe, we want it to work out, it's that sickeningly maddeningly unadulterated knee jerk orientation to life and driving need for good to triumpth over evil and puppy dogs to live forever and etc. etc. etc. that's in our marrow.
I think that drives some people nuts or at least gets on their nerves.
Seriously, happy people get on people's nerves.
And yeah, ENFPs can be childish as well as child-like.
Let's just say "youthful" and call it a day, shall we?
BTW, I've known an immature ENFP or two in my time. Well intentioned, sweet girl but hella annoying. She was all a whirlwind of (too much) energy and misdirected outbursts and poorly worded attempts at banter - almost like an untested ENTP (HAR HAR HAR) Sometimes her Ne would lead her out (way out) of the flow of conversation and she would basically take over the conversation to talk about some personal tangent that let people looking puzzled.
The funny thing is, she especially annoyed other EF and NF types! Hahahaha. Okay, I'm just being mean now. But, she did get along really well with the very laid back INTJ so maybe there's something there to type dynamics.
“If you want to tell people the truth, make them laugh, otherwise they'll kill you.” ― Oscar Wilde