So here is what I found to be thought-provoking.
Though I'm sure that those kids received more than one present, there were two that seemed to stand out in the narrative, . (I think a third one of a bicycle (I forget to whom) was also mentioned.)
One of these was the life-sized doll of a replica of JonBenet dressed in one of her costumes which, apparently Patsy had gone to great trouble to order and thought a lot of, whereas JonBenet was apparently not impressed by it. The remark is made that it's funny that gifts that the parents think will be a big deal - turn out to not be for the kids and it is either stated or implied that Patsy was disappointed by JonBenet's reaction.
We know that Burke, on the other hand, received that year's latest Nintendo set, which my then 8 year-old also wanted and got, and which he was so nuts about that I had a hard time separating him from that thing most of his waking hours. We know this because when Burke leaves the house, he takes it with him, which also points to his interest (and might be considered a bit strange to think of it if his sister has just been found dead but whatever ... maybe not).
Not much was said about the Nintendo set in the Ramsey book but those of you familiar with the gadget know that it was a huge hit with kids. The doll, however, received a fair amount of attention. I remember posts commenting on what a strange idea this gift was and I admit that I side with them. I think that the varying interest of these two gifts on the part of JonBenet could well have been the issue of a spat between brother and sister. On the other hand, it is also possible that Patsy, on that particular day, may have seen her daughter as an ungrateful little brat and not feeling much patience towards her. If memory serves, someone recalls JonBenet looking glum and when asked why, answering that she didn't feel pretty. Was this incited by a mother who was resenting her ungratefulness on that day?
I know some of you will think this is all meaningless, but I think the answers to this death lie on the state of mind of the Ramseys on that particular day - just like the OJ case - and fatal blows arising out of anger because someone lost it rely on the psychology of the moment.
P.S. What was Patsy thinking in making such a big deal about that gift? What was the child supposed to DO with it - as opposed to the brother's gift which was all about new and inventive interaction? I also think that this shows that the mother was much more obssessed with the pageant thing than the daughter may have been. Personally I think that the gift of a life-sized doll is somewhat creepy.
Edited to add: it also shows that the mother was out of touch with the child's interests and not happy with the daughter's behaviour not corresponding to her expectations.