I've known since day 1 that Sacha is smart as a whip. But he's demonstrated it more frequently since he started speaking. Now, it's official. You can't pass anything by this kid.
I noticed it first the other day when I was reading him his newest "favorite" story. It's about a St. Patrick's Day parade held by ants where they chase a green ant that is a leprechaun to hopefully snag some good luck. I was reading along and said, "'Green ant!' asked Grant." Sacha immediately interceded. "No, no. SAID. Not ASKED. SAID." Oh, yes, how silly of me. "Asked" is used in the next line. He's done this before where he knows a book so well that he'll correct you if you say it wrong. What came later though totally blew me away.
I was reading him a French book about a group of animals that each bring a different part to the party to help build a snowman. It became apparent to Sarah and me that whoever did the translation of this book into French didn't edit it very well because there are a few grammatical errors, one of which went unnoticed until our 3-year old grammar Nazi came along.
A little preamble is in order. In English, no matter whether you have one cat or numerous cats, you would still write "The cat places the carrot as the nose." OR "The cats place the carrot as the nose." The "place" changes to match the subject, but other than that, there is little change. In the case of French, the masculine definitive is "le" as in "the" but only when in reference to a masculine noun (English does not have this gender differentiation of nouns). If it is before a single subject like "chaton" (a single cat) it is "le chaton". If it is before a plural subject like "chatons" (two or more cats) it is "les chatons". You can see how the definitive changes its state to match the quantity of the subject.
So I had read the line "Les chatons place le carrotte pour le nez" numerous times without protests and without noticing anything. Then after correcting me on a few errors earlier on in the book (which I had made due to extreme fatigue) Sacha started to protest vehemently. Previously he had asked me to stop saying "chaton" because he preferred "chat" as he did not feel that this particular feline was worthy of being called a kitten (chaton). I thought that's what this particular protest was about so I said, "Oh, right "Les chats place le carrotte pour le nez"". "No, no, no, only one chat." Then I looked, and sure enough, there it was. The illustration only featured a single cat. Therefore, the phrase "les chats" is grammatically incorrect. And my 3-year old called me AND the editing staff of the book on it. Look out future teachers. You'd better be on your game!