Sentence 1: Cass was very thirsty. 
 Sentence 3: Cass decided to handle both problems at once 
 Sentence 4:  She made a thick milkshake 
 Sentence 5:  She drank it to relieve her thirst AND her craving for sweets! 
 Option 1: But she wanted dessert too, since dinner had just ended. 
 Option 2: So she grabbed a glass of milk.