> Be careful with the word "fluent". It's often overused and misused. And it
> does a disservice to those who *are* fluent.

Well, this is 'fluent' at a low level since they are 3 and 6. I have seen
young kids whose Japanese was at the same conversational level as that of
their native counterparts after a year.
What about the overused expression of "bilingual" or "trilingual"? In most
cases foreign kids will be fluent in conversional Japanese, but reading and
writing is another issue.

Sigi