This is a great article that sums up very well the issues involved in raising bilingual children. Many of the people that my son and I communicate with in Japan, teachers included, think that learning another language as your first is genetic. "Oh, your father is American, you must speak English," they say. The only reason that my son is bilingual is because he has done the hard work and my wife and I have advocated for him every step of the way.
The only reason that Japanese parents don't do the same thing is because they believe, unfortunately, that they can't. Sorry about that, but I have three all together, and we'll make sure they get the gift of bilingualism.
Raising bilingual children takes time, huge effort — and lotsa money | The Japan Times Online