Perhaps it is so that people, and yes, certain children are more sensitive in wanting to communicate in a 'community language', say English, in australia, when with others, but on their own, they will revert to their own home dialects.
I say sensitive, as I have some girls, who keep giggling in Indonesian non stop once I start a few words in Malay to them. And these girls are competent in English as well.
So when dealing with the more sensitive personalities in public, I will use the 'community language' with them. But on a one to one basis, we revert to 'home dialect' as the child chooses.
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