The other day, I was in a supermarket, where I ended up on one of those parallel shopping experiences (you know, where you're both going up and down the aisles in a leapfrogging but more or less same place, same rate pattern) with a woman and her maybe 10 month old child. Early on in the shopping trip, she did a strange thing: The child had done something (which I didn't see) that required correction, so the mom said, quite emphatically, "Fwee! Fwee!" In this context, "fwee" (or however one would spell it) clearly meant "No!" The rest of the woman's conversation with her child was in English, so my first thought that this was a language I didn't know seemed not to be supported.
Is there some language in which "fwee" or something like that means "no"? And if not, what gives? Is this just some silly way of telling your kid no without teaching him/her the useful word "no"? Or what??