answer: #Person2# gives #Person1# two pills to treat #Person1#'s brother's carsickness, but #Person2# finds that #Person2# gave sleeping pills that have no undesirable side-effects by mistake.
documents: #Person1#: Excuse me? Do you have anything for a carsickness? 
  #Person2#: Yes, but you look fine. 
  #Person1#: Oh, it's for my brother. The little boy over there. He is getting a carsickness. 
  #Person2#: Poor boy! But don't worry. Here are two pills made in Germany. It's really effective. He will be just fine. 
  #Person1#: Thank you so much. 
  #Person2#: Take some with you next time, just in case. 
  #Person1#: Sorry to interrupt, but my brother is still sleeping. 
  #Person2#: You mean the boy who felt carsick just now? 
  #Person1#: Yes. It's so strange that he slept all the time after taking the pills. 
  #Person2#: Oh, sorry, maybe I gave you the wrong medicine. 
  #Person1#: What? 
  #Person2#: It's just sleeping pills made in America which is also very good. But don't worry. It has no undesirable side-effects. 
  #Person1#: I see.