Sentence 1: Kate's sister wanted them to have matching butterfly robes. 
 Sentence 3: Kate didn't want the frog one they had in stock 
 Sentence 4:  But her sister wanted her to have one 
 Sentence 5:  So Kate went ahead and bought the ugly frog robe 
 Option 1: But the butterfly robes were sold out. 
 Option 2: The butterfly robes were available at the store.