In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.

Let me give you an example: Passage: Nearing London, Oliver encounters Jack Dawkins, a pickpocket more commonly known by the nickname the "Artful Dodger", and his sidekick, a boy of a humorous nature named Charley Bates, but Oliver's innocent and trusting nature fails to see any dishonesty in their actions. The Dodger provides Oliver with a free meal and tells him of a gentleman in London who will "give him lodgings for nothing, and never ask for change". Grateful for the unexpected assistance, Oliver follows the Dodger to the "old gentleman's" residence. In this way Oliver unwittingly falls in with an infamous Jewish criminal known as Fagin, the gentleman of whom the Artful Dodger spoke. Ensnared, Oliver lives with Fagin and his gang of juvenile pickpockets in their lair at Saffron Hill for some time, unaware of their criminal occupations. He believes they make wallets and handkerchiefs.
The answer to this example can be: Who believes Fagin's gang make wallets and handkerchiefs?.
Here is why: This question is based on the following sentence in the passage "He believes they make wallets and handkerchiefs". It evaluates the understanding that the pronoun "he" refers to name "Oliver". You can ask questions like this one about most pronouns in a paragraph.

OK. solve this:
Passage: The film concerns the story of the Boyajian family, who have not celebrated Christmas in 11 years, since their son John was killed shortly before Christmas in 1991 during the Gulf War. With their daughter Jeanie potentially facing a life-threatening illness, George decides they should once again celebrate Christmas; however, Carol adamantly refuses.
George heads to watch over the town's veterans memorial and is accosted by several teenage punks, who are scared off by "Matthew," a hitchhiker passing through town. As Matthew and George talk, Matthew claims to be a Gulf veteran who is the same age as John and served in the same regiment as John, although the two did not apparently know each other.
George invites Matthew to spend Christmas with his family, asking him to tell his wife and daughter that he knew John while they served together. George's ultimate plan is to get the family to once again celebrate Christmas, which works. But as Matthew makes up stories about himself and John, George begins to wonder about Matthew's true identity when his stories include details that only John would have known (including a notable surgical scar from an athletic injury).
At the end, it is revealed that Matthew is actually John  making a supernatural visit (by revealing the scar mentioned earlier) in order to restore the family's Christmas spirit.
Answer:
Whose son was killed in 1991?