Sentence 1: Anna always hated her big sister. 
 Sentence 3: Even in high school, they bickered constantly 
 Sentence 4:  But as they grew into adults, they became friends 
 Sentence 5:  Eventually Anna realized her big sister was her very best friend 
 Option 1: As kids, they did nothing but fight. 
 Option 2: They got into a fight and never spoke again.