So primary issue with “Kevin is dead” theory…
The oldest daughter does a count of the kids and mistakenly counts the kid next door who was bumbling around the passenger van. The mom then asks how many she counted and she says the number which would have to include Kevin.
The issue for the film’s premise of him being left home alone is also a huge plot hole for the same reason. Once they would have gotten to the airport, Kevin would have had to have been there and accounted for his ticket to get on the plane. Even back in the 80’s/90’s that was standard practice for a passenger to board with ticket in hand. So they would have known before getting on the plane that Kevin was not there.
Additionally as mentioned by @gracchus the theory that Kevin’s dad is a mobster is also completely blown. First and foremost the “Wet Bandits” would have known NOT to rob that house as experienced burglars in that city they’d know who is connected and who to steer clear from. Additionally, if he was mob boss, the mom wouldn’t have called the police to check on Kevin…the dad would have called “one of his guys” to go to the house.
Not to squash the fun of fan theorizing…sometimes a cake is just a cake. Some theories are completely fun and they help make a story better by answering unanswered questions or irrelevant questions (see: The Dark Knight fan theory that the Joker is a wounded special forces veteran, or the connected Pixar/Disney film theories. I especially like the Little Mermaid, Tangled, Tarzan, Frozen connections); however, some are just over thinking things. Home Alone fan theories are in the later category IMO.
It’s meant to be a homage to Bugs Bunny/Road Runner/Tom & Jerry Chuck Jone’s style cartoons. Yes it is unrealistic and not remotely what would happen to 99.99% of kids left home alone…but its fun and makes for great laughs. Especially everything Daniel Stern does throughout the film…
