Millie Muldoon & the Christmas Mystery

Is something wrong with Santa Claus? He stopped at their house on Christmas Eve. He ate the cookies and drank the milk they put out for him. But he didn't fill their stockings or leave them any presents. Why? Was Santa getting forgetful? Was there an emergency back at the North Pole? Could he have put them on his naughty list by mistake? Millie needs to use her detective skills to solve the mystery of the missing presents before Christmas is ruined!