While most people are relatively aware of the general surface-level emotional state of others, and can take it into account, some people are sensitive to the subtle moods and feelings of others to the point of taking on that emotion themselves, even from childhood...
So I thought I'd share my experiences as an emotionally sensitive child here, in case it resounds with anyone, or helps anyone who has a child who seems more sensitive than most! :O)
Most children have the ability to identify basic displays of emotion from others (if they can slow down their busy play long enough to notice! :D), and to respond with a kind and socially
appropriate response (often with a little coaching and training for more logic-oriented kids).
Being a really empathetic child is a totally different life experience, from my own life observation. An empathetic child runs into a room with her friends at a playdate, and all the other kids are honed in on getting their needs met, saying hi to mom, or continuing the sword fight...but the empathetic child has been plunged into another emotional world entirely.
All at once, s/he is aware that the grandmother in the corner is lonely and feeling irrelevant, mom's friend is acting tough to hide her insecurities, mom is overwhelmed with pride for her new baby, father is anxious at having his space invaded by so many people, auntie needs to feel important...however, being very young, the child, of course lacks the vocabulary to express the specific ideas. But, the emotions, being emotions, are felt and understood, even though immaturity limits the ability to understand why or process it appropriately.
Obviously, personality, culture and age probably dictate how the child responds to the information overload. As a child/teen/college student, I was often accused by my friends of being aloof, "ditsy", quiet, meek (I still guffaw inwardly at that one), head-in-the-clouds, quirky, mysterious, weird, snobby or distant. :P (Somehow, though, I managed to have no shortage of friends, probably because I was really good at anticipating their emotional needs!)
The thing that I did most often (and probably still do) appearedto be dawdling/procrastinating/daydreaming on the surface. Indeed, getting me to make it on time to ANYWHERE was almost impossible.
The reason for this was usually that I needed massive amount of time to process (often through play, talking to the mirror, sleep, rehearsing conversations in my head) all the emotional information I was receiving. Trying to explain that to anyone else was like trying to nail butterscotch pudding to the wall; all the action and logic and intelligence was not only happening on the inside, but I also was processing things that others didn't observe easily. I may as well have been trying describe a platypus to a martian in Russian. :OP
Empathetic children can appear inflexible or inexplicably moody, because what's effecting them emotionally doesn't always originate from them or observable interaction. They wear out quickly in large crowds or in intense emotional situations, and can burst into tears or grumpiness seemingly out of the blue.
I lived with the constant nagging terror that others were as aware of me and my emotions as I was of theirs, which led to all sorts of funny self-talks and rituals and self-protective efforts.
Trying to pay attention to verbal instruction was near impossible as well; the speaker would be instructing away about a specific set of concrete directions, and the information I was receiving was their emotional state at the moment. I was getting information LOUD and clear, but, unfortunately, what my brain naturally honed in on wasn't the information they were trying to communicate. At the end, they'd say, "Do you understand?", I felt, "Please, please understand so I don't have to say all that again", and so, I'd agreeably nod yes to their feeling, not their words. If I could sense that they honestly didn't mind repeating it, or if they actually enjoyed hearing themselves talk, I'd ask for them to repeat it, go through the whole scenario again, reach the end again, and think, "DAMMIT! I missed it AGAIN!!" Frustration. :P
Books were my friends. :D
I've noticed that my own daughter often responds by ignoring me, if I'm emotionally keyed up myself. We've talked about it, and here's her reason: she feels like I'm invading her emotional space when I'm upset or angry, because she senses it in her own body so strongly. It's a self-protective measure..not because there's anything wrong with her knowing that I have feelings, but because she feels them so acutely, she doesn't yet know how to process them and set appropriate emotional boundaries. (Fwiw, with this particular child especially, I make an effort to not be demonstrative with my anger or raise my voice...she's honestly just that sensitive.)
In short, people were both the bane of my existence and the beauty that my world revolved around. Even when I appeared to not be listening or at all connected, I was possibly more connected than most...though it probably took some time to come to fruition. I smile and cringe when I see similar traits in my own daughter, and am thankful that I at least have something useful to pass on to her-the empathy of what it feels like to be empathetic. ;P