A Centaur

Stardust thinks it over "A Centaur." She replies "They have a voice and can stand on 4, 2 and 3 legs"

"Not quite" You reply "I see your reasoning but this is a creature that uses a different number of limbs as it grows If the answer was a creature with 4 legs that can stand on 2or 3 then that would include many creatures including dragons who also have a voice. The correct answer is Human."

"How?" asks Stardust confused.

"You see us humans start by crawling on our arms and legs as babies then learn to walk on two legs as an adult then when we grow old we require the use of a walking stick, a stick we use to extend the reach of one of our arms to walk upright with increased support that our bodies can no longer supply. "

"That was a quick game and it looks like you win. You Win both myself and the princess to do with as you wish"