Not content with being trilingual, our children have taken to inventing their own language. And I don't just mean mispronouncing words (that they do in spades too: the most common one is "klokat" for chocolate, but only when they speak in English. "Chocolat" in French and "Schokolade" in German mostly come out properly. Bizarrely though, a couple of their friends apparently use the same word for chocolate too, although they may speak French, Dutch or Spanish. One mother explained to me that they all picked it up from a Greek boy in Leonard's nursery group who used the Greek word for chocolate, which apparently sounds something like "klokat"). No, my children will say to each other "Shall we talk in a different language?" And they then proceed to throw gobbledygook sentences at each other, sometimes with a questioning intonation, sometimes not, but very often jabbing at the air with their first fingers as if making a point, or actually pointing at something. And they think it's even more hilarious if we join in.
Today I was listening to their pronounciation in their invented language, and I noticed that while the consonants were not markedly English, French or German, the vowels were definitely not English - no diphthongs! I think this strengthens my thesis that, for the moment anyway, English is probably closest to being their mother tongue, if you assume that they were putting a "foreign" pronounciation into their invented language. They don't have any vocabulary that regularly crops up in their language i.e. a particular word that comes back for a specific thing - they are only 3 and 4 years old! But I think it still shows an amazing metalinguistic awareness, for example of the fact that there are different languages and how you can simulate one in a very basic way.
But one thing that does happen in the multilingual environments that they inhabit, is that they do pick bits of other languages and they are mostly aware that they're speaking another language. I overheard them singing the tune to "Happy birthday to you" while they were doing something else the other day, but with different words. And as I listened, I slowly realised that it wasn't gibberish, or mistreated English, French or German but "Cumpleaños feliz". The only Spanish they hear is from friends at nursery - isn't that cool, that they picked that up, just like that? So I pointed out to them that it was Spanish and mentioned their Spanish-speaking friends. The funny thing is that now sometimes they'll say to each other "Shall we speak Spanish?" and then launch into their gobbledygook language. Cos they know that they don't speak Spanish.