My American child taught me that saying “baseball ball” is wrong. The name of the ball is baseball. Weird as that is.
She’s also teaching me the correct American intonation patterns. I try to imitate her but, as a native speaker of Russian, I have a very flat natural intonation. At least, I’m Ukrainian and not Russian, so my affect isn’t flat.
On my part, I teach her to range problems in the hierarchy of importance because she already started picking up at school the idea that everything is “a horrific problem that hurt my feelings.” Also, I’m teaching her that difference of opinion among friends isn’t a catastrophe but something normal and actually good.