"I have a little smart bird. It can dance."
I've always understood that 的 is required after adjectives of more than one syllable. I could be wrong, but it says the same thing here:
The English has a big problem: the order of adjectives. If you are a native speaker you might not notice that adjectives have a correct order when appearing together to modify a single proceeding noun. Quality (smart) ALWAYS precedes size (little). likewise, size precedes age: big young man, little old lady 等 does anyone say young big man.. No, unless big man is a noun phrase, like 'smart phone' for example