Crossword puzzle clue "what has sixteen legs and sings"

What has sixteen legs and sings?

"I go on four legs in the morning, on two legs in the afternoon, and on three legs in the evening ..."

Von Trapp girl who sings "Sixteen Going on Seventeen" with Rolf

Source of the maxim "Four legs good, two legs bad"

A pint has sixteen: Abbr.

It has legs and feet and sometimes arms, but no hands

It has short legs and a long body

It has arms, legs and feet, but no hands