How cute! I love the exaggerated expression. The color pallet is nice and calm too.
The only things I see that stand out to me are the lines in their ears, and the overly yellow color of the background. You could say that i'm nit-picking by this point, and I probably am, but I just couldn't help but notice, aha. The background just seems a bit too yellow, because the rest of the piece is so calm with a pastel cyan for skin.Other than that, its a really nice and calm piece, despite the background.