Children individuate in stages. Primarily there are two. At ages 5-7
approximately children become individuals. This may sound strange, but
you'll find evidence if you observe carefully.
At first, a child really recognizes two entities, himself and everything
else. Although there are highly identifiable parts of "everything else,"
like mom, etc., the child cannot really understand them as separate
individuals. Little ones of these early ages may be unthinkingly cruel,
because they do not recognize others as beings who can be hurt. One
little tyke at our house on a visit was hurting some kittens. She said,
"squeeze it and it talks." Well, of course it did. We had to explain
"How to treat kitty." The least bit of empathy would prevent this
treatment, but this little girl, probably about three at the time, was
not yet capable of understanding.
As an aside, many daycare facilities talk about "teaching children to
share." Before a certain age, it's futile at best.
Another thing you may have observed. Young children sitting together,
with a common pile of blocks, plastic animals, whatever. Each child is
playing his/her own little scenario, totally unrelated to the others.
Psychologists call this "parallel play," because there's little or no
interaction between/among the children. Often, the only interaction that
this produces is a quarrel. These children have not yet individuated,
come to see themselves as individuals like others, and become capable of
sharing, taking turns, empathy, etc. Attempting to force these concepts
too early may result in a sort of wooden compliance, but not
comprehension and understanding.
Someone once asked me if we can't affect readiness and development. I
thought a second, and said, "We can delay it." If we provide the optimum
environment for the child, he will naturally develop at his maximum
rate. Alas, we do many things which detract from that optimum
environment, often in the name of "speeding up development."
Famed psychologist Jean Piaget was once asked, "Is there any way to
speed up development?" to which he replied, "Why would you want to do
that?" To everything [in child development] there is a season, and a
time to every purpose under heaven.
Oddly enough we traditionally send children to school just as they are
about to individuate, with catastrophic effect on their search for
identity.