* Buzz is able to convince Kevin that Old Man Marley killed his entire family because Marley hasn't been visited by his family since before Kevin's family moved to the neighborhood.
* After finding out what he thinks that he made his family disappeared, Kevin has memories of mean things his family said to him. Out of all of what they said in his mind, the only part that didn't happen was when Buzz says "Kevin, I'm gonna feed you to my tarantula". Even though he never said that to Kevin, it's actually all in his mind including the way the others said to Kevin which motivated him to enjoy being alone.
* Harry and Marv seem to get dumber and dumber to the point of Flanderization. Then again, they have had a LOT of head injuries...
--> Harry: Don't you remember what happened last year!?
--> Marv: ...No?
** Marv is the only one who seems to get dumber between the two films, but then he does indeed suffer more head blows than his partner. Harry actually anticipates some of the traps in the second film, though he doesn't count on them being modified.
* Why Harry didn't notice his head was on fire in the second film may seem like RuleOfFunny at first. However, because he had his head set on fire before, the nerve endings could be permanently damaged. So he probably couldn't even feel it till he saw it.
* When Kevin tells his family that he just "hung around" while they were gone, he's referring to when Harry and Marv hung him up on the door, prior to Marley saving him.
* At the end of the third movie, the spies catch Alex's chicken pox. Chicken pox can be lethal for adults.
** Chicken Pox is ''very'' contagious for about 8 days (2 before the spots show and around 6 after). His siblings were still around him. Even if they've had it before, could they maybe have given it to kids at their school?
* Near the end of the second movie, Kevin escapes his uncle's house by dangling a rope over the edge of the roof, climbing down said rope, and then lighting it on fire when Harry and Marv try to climb down after him, causing them to crash through the scaffolding and get covered in varnish. Unless one of the neighbors immediately noticed the fire and called the police, that fire is going to spread to the house itself and, since it's a townhouse, probably to the other residences. And if the neighbors are at home in bed asleep...
** Unless they had smoke detectors (though a housefire on Christmas is still an upsetting thought).
** It seems like a bad neighbourhood; most of the houses look empty. Plus, the paint and the fall might have put the fire out. Harry and Marv weren't set alight when the rope fell, after all.
*** It's actually an affluent neighborhood of brick townhouses, with expensive cars on the street and lots of houses with holiday lights. Which makes nobody noticing all that's going on even stranger.
* The blowtorch gag from the first movie. Thank goodness Harry was the one to go through that door, and he just got the top of his head burned. If it had been the much taller Marv, that would have been his ''face''.
* In the second movie after defeating Harry and Marv, where was Kevin planning on spending the night? He obviously couldn't have known his mom would find him in Rockefeller Center, he couldn't go back to the Plaza Hotel or any hotel seeing as his dad's card was put on hold, and probably thought he was wanted by the cops. It was below freezing that Christmas Eve (remember the frozen puddle), and he didn't exactly look overdressed. Plus all the few warm spots like subway gratings and vents would be occupied by potentially mentally ill homeless people. "It's scary out there", indeed.
** Because he's established "the pigeon lady" as a friend, he could go and thank her for rescuing him and then she would surely allow him to stay at her little room above the symphony hall.
* Despite how dumb they are, Harry and Marv were still smart enough to escape from prison. If they escaped again after the second movie, Kevin would be in a huge amount of danger, since they know where he lives, know how to acquire a gun, and really, REALLY want him dead.
* What was stopping Kevin from calling the police?
** Being an 8-year old and fearing the burglars who are gonna break into your house.
** He also shoplifted a toothbrush in the first movie, and was chased out of a 4-star hotel for credit card fraud in the second movie; as a kid, he might think he's still in deep trouble afterwards...
** They say near the beginning that the tree that ruined the power lines and made them late also ruined the phone lines. And all the neighbors are gone for vacation. Why Kevin doesn't go to the store or the church that he is apparently in walking distance of is anybody's guess.
** In the first film, Kevin clearly sees Harry dressed as a police officer, that may have played a role.
** I would say this is because he truly believes he has magically made his family disappear, which the police couldn't fix. Notice he asks the guy who he believes works for Santa for his family to return.
* Kate didn't really need the Polka King: why couldn't she just rent her own car and drive herself?
** Because she gave all her money and jewelry to that old couple in exchange for their plane ticket, and she was exhausted from traveling. Plus, renting a car would mean returning it, so she couldn't do that either.
** In addition, debit cards do not exist and only few high end places would accept credit cards. I suspect that interstate car rentals were very rare too since Onstar, GPS, or any tracking system was non-existent.
* On another note, New York in the second movie somehow becomes completely deserted, but only when Kevin faces off against Harry and Marv (the rest of the film correctly shows crowds of people). And this is the "City That Never Sleeps"!
** This troper has admittedly never been to NYC, but Kevin faces off against Marv and Harry on Christmas Eve. Would that possibly have had any effect on the crowd? Certainly more places would be closed, at least.
* In the first movie Kevin's 8 and in the second movie he's 10, meaning it's two years after the first. So why is everyone referring to the events of the first film as ''last year''?
** This might actually be FridgeBrilliance, [[InsaneTrollLogic Kevin may have been born on February 29th and his parents may only celebrate his birthday every two years as a compromise.]]
** That may have been a last minute script change, or an oversight.
** It does work if the first movie was just before his birthday, and the second just after.
** It ''is'' the same general time of the year, but if Kevin's birthday was on a fixed calendrical date after the family left the first year and before they left in the second movie, it works.
** The only evidence we have of his age in the second film is his word; Kevin may have altered it himself, for whatever reason.
** In the novelization of the second film the family is leaving after Kevin's birthday (the Talkboy was a gift from his grandmother) and talks about the previous year's mishap where it's explicitly stated they left ''before'' his birthday.
* In Home Alone 3 how sick was the kid? We never see anything more than spots on him and yet he has chicken pox. He should at least have occasionally scratched a bit, but he's running around the house like he's healthy on the fifth day. Yes, technically antibiotics can make you feel okay while still contagious, but there was no indication that he was sick at all, which is weird since ''it's the whole reason he was home alone.'' I'm not asking for debilitating or anything, but a reminder or two during the film of "oh, right, he's sort of got one of the worse diseases a kid can have" may have been nice.
** He is itchy, though. Mrs. Hess calls him out on "scratching in front of a lady", his parents tell him not to scratch, and his brother makes a joke about the resulting scars. They probably, off-screen, slathered him in calamine lotion and had him take oatmeal baths (which really cuts down on the itching). [[labelnote: Personal Anecdote]] My sister and myself both went through chicken pox (two seperate incidents at 9 and 5 respectively) and it barely slowed us down, itchy but that's about it. My mother, on the other hand, at 30-something was bedridden.[[/labelnote]]
* Marv's an idiot, and while Harry's not much better, he has his clever moments (in the first movie, anyways). How is it that his only argument against Marv flooding each house they steal from is that it's a "sick thing to do"? You'd think that Harry would know that, not only would the police know each house they stole from thanks to the flooding, but they'd also get the two with destruction of property thanks to flood damage.
** The police say they know what houses they robbed thanks to the flooding, but some of it could have been copycats. It probably wouldn't stand up in court as proof.
** Harry doesn't think they're going to get caught. If they do, there is probably going to be more than enough evidence against them even without the flooding (though obviously that doesn't help- and copycats are EXTREMELY unlikely, plus the flooding would not be the only proof and it WOULD stand in court) to put them away for a long time. His main concern is that even without the risk of capture, it's still unhealthy...and hey, maybe this is even a case of EvenEvilHasStandards, since while he has no problems robbing houses for profit (and he wasn't yet ready to kill a kid- they probably originally planned to just tie Kevin up and otherwise leave him be if he hadn't tortured them first), flooding and wrecking their homes for no reason other than "It's our calling card" might be a step too far even for him.
* If Alex had to press the record button to get footage, wouldn't that have given away his position to the spies when they reviewed the tape?
[[WMG: Sort of FridgeLogic]]
* (Putting it here before it comes up:) The dog door on the the backdoor of the [=McCallister=]'s home. They have it because they have a dog (that we never see), Kate mentions that it's in the kennel when she's on the phone at the very beginning of the movie (just before telling Kevin to get off the bed).
** Of course, that brings up the question (as any pet owner would notice) where is the rest of the dog's things (toys, etc)? They wouldn't have brought it all to the kennel. Also, it's never mentioned in the second film.
*** Some families keep all their dog's toys in a basket when the dog's not using them (so no one trips on them), and train the dog to just get them out of the basket if they want anything. If the dog's not there, they may have put the basket in a closet or something.
** Given how crowded the house was with guests, and the possibility one of those guests might have been allergic or just didn't like dogs, they might've exiled the family pet to the backyard for the few days prior to their flight. Putting its toys outside with it would help lessen the sting of being evicted.
** They could also put the dog in a Kennel because most flights don't allow dogs.
*** Actually, given how many relatives they had to deal with, they probably had an unusual attack of practicality and put the dog into kennels a day or two before they left to make preparations smoother. Flying to France with a largish dog is not terribly easy at the best of times.
* Why doesn't Kevin call for help from somewhere with a working phone, like the grocery store? I would say this is because he truly believes he has magically made his family disappear, which the police couldn't fix. Notice he asks the guy who he believes works for Santa for his family to return.