A: Dear Glennmatt:
Your son is lucky! Little children--up to about the age of five--have an extraordinary capacity to learn languages, which older children and adults somehow lack. So this is a great age to have your son acquire the Korean language as well as English. It appears that children of this age seem to manage the process of learning multiple languages pretty well, so I would not anticipate problems.
Speaking Korean and English will help your son feel securely planted in both sides of his parental heritage; this is also a good thing for him psychologically. And of course, from a practical perspective, it is an increasingly useful skill to speak more than one language as our globe becomes smaller and smaller.
Elizabeth Berger MD
Child Psychiatrist and author of "Raising Kids with Character"