Sentence 1: Jake and his grandfather were spending the day together. 
 Sentence 3: He brought it out and Jake's eyes lit up like stars 
 Sentence 4:  Jake and his grandfather spent the whole day talking and building 
 Sentence 5:  They had a wonderful day together bonding over the train set 
 Option 1: They went to the park together. 
 Option 2: Jake's grandfather had already planned ahead and bought a train set.