Thanks for the kind words, I am glad this helped. Now that I know you have 3 languages to contend with, I would advise you to reduce your anxiety about the late language development dramatically, it is extremely normal and understandable.
Here is how I think of this process they are going through.
First phase is passive, i.e., they understand far more than they can say. Think of words as “bricks” of information. The more bricks they understand the better. At first all the bricks are the same, let’s say the same color, no matter what language was spoken, and they are attaching meaning to those words. Soon they find that some “things” have multiple words that apply (Water, agua, shui). They attach more words to the same meaning (even within a language there are multiple ways to describe something).
They imitate sounds, watching carefully the faces (visual feedback very important in them learning to speak) and get positive responses. Perhaps Grandma understands only Chinese, and responds to the child imitating words in Chinese, positive response, interaction, and perhaps getting some water (shui). The child might try it again with dad, but it does not work, only “water” works with him, and now the child begins to notice that certain people only understand certain “colored” bricks of information. They can feel that certain words “sound” or “feel” like Chinese/Grandma words, others feel like English/Daddy words, and they begin to segment their vocabulary.
Understand at this point they have 2 or 3 words for every meaning they learn! They start to sort these things, but it is very mysterious, as word order, blending of words, time of interaction all are different.
At a certain point however, they realize that not only does Grandma “like” certain colored bricks, she doesn’t understand other colored bricks, and one day spontaneously the child “helps” grandma in a conversation when daddy speaks of water, the child tells grandma very helpfully “that means shui!”. They begin finally to speak, having finally figured out that there are different sets of bricks that go with different people, and some people understand only some of the bricks, others don’t. IF there is a language that EVERYONE in the household understands, that (in order to simplify) becomes their spoken language of preference. They UNDERSTAND Chinese and Portuguese, but speak only English (IF YOU LET THEM).
Here is the challenge. To this day my wife insists that the children speak to her in Portuguese (if they want to please her or eat, or get a ride, or ask a question), in other words, Portuguese is mandatory in our house. Because we live in the states, English is everywhere, the media, school, their cousins, friends, etc., but we actively promote their native (mother) tongue to keep them both bilingual and bicultural. This pays HUGE dividends when their cousins visit, or we go to Brazil, and they now have approximately TWICE the vocabulary of most kids their age, and they know that there is no “one” way or “one” culture.
Grammar sorts itself out, with kind of constant word order confusions, but accents are very slight if at all. Some odd expressions come through unfiltered translated literally from the other language, but this just makes us laugh. They have a great ear for other languages, and like I said, they OVER communicate.
So, passive vocabulary first, all just “words”, differentiation of different “flavors” or “colors” of words, then tentative experiments to test “theories” (Does shui mean “water”?), then using only certain “flavor” words with certain people, and then actually translating for some of those people, and then trying to find a common denominator language that everyone understands to simplify their speaking task. If this is not possible, or not allowed, they just learn two or three languages, not just one, but realize they are doing 2 or 3 times the work of a one language household child, and so it will take a bit to sort it all out.
Here is the most important part. They DO “sort it all out” and then they are bi-lingual, or even tri-lingual, and fluent. Their minds are much more versatile, they have multiple “communication strategies” because they needed them.
Hope this helps,
Chris