I have some answers, from my experience: Let’s go back to the minute he
(our son) was borne. Baby pops out and the doctor lays him on mom’s chest, she starts cooing to him in Portuguese. Some minutes later, time to time to meet dad, as I’m holding him, I coo to him in English - and that is the way it has always been. The first 2 and a half years of his life, the day care center and lots of his social contacts in Southern California were Brazilians, mom also only spoke to him in Portuguese. But all his Television, videos and such were in English, as well as all interaction with me.
FF 5 years. We now live in Brazil. He goes to a Brazilian school and all his friends are Brazilian, so he speaks Portuguese with no accent, you wouldn’t know he was not Brazilian even if you are. At home we only converse in English, yet he and his mom only converse in Portuguese (even at the dinner table). So I might say “Pass the salad” in English to him, but his mom would say the same thing in Portuguese. He would respond to me in English and her in Portuguese, but my wife and I only converse in English, and he absorbs that as well.
Still ALL kid vids, Television, conversation with me and his mom together are in English. He has no accent, you would not know he spent more years in Brazil than in the US. The duel languages thing seems to need to be constant, and not at set intervals, like special classes and what not, 50/50 seems to be the way to go. Also having lived in 2 countries probably helped as well.
Now a days at 7, he gets lazy with the languages, mixing Portuguese verbs in his English sentences, so he might say “Dad, what’s “Escret” here", I say what? Then he might say “I mean, what’s written here”, have to always correct this or he may develop poor language habits.
We were worried that this system may have some unforeseen ill effect, but at this point there is none evident, its just the way of life around our house. In fact, he seems to be able to grasp abstract concepts better then you would expect, but that may just be a proud daddy crowing about a kid who is smarter then he was. A Psychiatrist I used to work with said that as the brain develops we assign names to sounds and images we see daily. A mono lingual person hears a “Meaouwww” and sees a 4 legged fuzzy animal, mom and dad say “nice kitty” so we learn the thing is a “kitty”, but in a house where one group of information says “kitty” and another says “Gato” the person learns 2 words for “Cat” and for all other things too. As the language centers grow and the persons conversational skills grow more complex, the person learns two groups of words that signify the same thoughts and meanings, and uses these selectively depending on whom they are talking to. Again, I have nothing to support the above theory except my own experience. And the words of the Shrink I worked with.
We have been told by his teachers here that in their experience its best to alphabetize a child in only one language, then when the information is solid in the kid’s head, start formally teaching the other language. So for now all ‘readin ‘writen and ‘rithmatic are in Portuguese, when he gets older we will start formal English classes.
In any case he has turned just fine. But you never know, he may just sprout a third eye yet, I’ll keep you posted.