The person had still not responded to Mable at all, only moving their hands and head as she spoke.  For a moment, Mable stared at them with a single brow raised.  She repeated the whistling gesture they made.

"Whistling," she repeated.  "Can you teach me, or are you mute?"  If they were mute, it would be very hard to learn, but Mable was willing to try anything to whistle!  She stuck out her hand and offered the person a small smile.

"My name is Mable!  Mable."  her other hand touched her chest.  "What is your name?"