arms. you may want to avoid trying to put her hands behind her back, though. she also demonstrates very clear articulation of the words by exaggerating them with her mouth and lips. this helps baby learn how to speak. try exaggerating the movements of your mouth as you speak the rhyme with baby. your face will be close to hers as you move her arms, so she can see how you are creating these interesting sounds.
baby songs often involve hand gestures, which babies love! the song “wind the bobbin up” is a fantastic rhyme to sing to baby while teaching her to bring her hands in front of her. if 