Sentence 1: Jen was 20 when her sister died from cancer. 
 Sentence 3: They went to live in Jen's one bedroom apartment in the city 
 Sentence 4:  There were a lot of tears and misunderstanding 
 Sentence 5:  Ultimately, Jen felt she did her best for her niece 
 Option 1: Jen's niece moved into her house after Jen became her guardian. 
 Option 2: Jen became the guardian of her 3 year old niece.