Hello In There: A Big Sister's Book Of Waiting by Jo Witek

A sister-to-be is so eager to step into her role that she’s starting early! She sticks close to her mama so she can sing songs to her sibling-to-be (loudly, of course) and explain all the great things waiting in the outside world (cupcakes! strawberries! swimming!).
 
With quaint line drawings, lovely patterns, and a variety of playful flaps showing the new baby blissfully tucked away in its mama’s belly, this interactive picture book is a joyful and celebratory ode to a growing family and the perfect gift for any big-sibling-to-be.