Step 15: Use the main circle as a guide to draw Jack-Jack's head. Darken the top edge of the circle to create the shape of the head. Follow the basic path of the bottom edge of the circle to draw the rest of the head. Make the side narrower than the circle. The bottom should almost be pointy for the chin.
Step 16: On top of the head, draw a couple of lines that curve up to a pointy tip for Jack-Jack's hair.
Step 17: Use the two sloping lines on the left side of the body as guides to draw Jack-Jack's first arm. Darken the guides but make them wavier to represent cloth.
Step 18: Add a small line to the top of the initial circle to create the cuff. Darken the lower edge of the circle to create the fist. Add a curved line on the right for Jack-Jack's folded fingers.
Step 19: Darken the sloping lines on the right side to create Jack-Jack's second arm. Make the lines wavier for the cloth. Darken the lower, left edge of the small circle for the cuff.