Sentence 1: Tim went to a friends house. 
 Sentence 3: His mom always said that his friend had a lovely house 
 Sentence 4:  Tim decided to clean up his own house 
 Sentence 5:  His mother was happy that she finally had a lovely house 
 Option 1: Tim went with his mom. 
 Option 2: His mom recently died so he was dropped of by an aunt.