Question: Maybe I missed it, but did the McAllisters even bother to call home? I don't remember them calling the house at all. Why wouldn't that be the first thing they do? Kevin seems to be pretty independent for his age. He might have not answered the door, but I'm sure he would have answered the phone.
Answer: They did but the power and phone lines were down due to a tree branch that had fallen on them the night before the family left. A flight attendant on their plane mentions that attempts had been made to call the McAllisters' home but "the phones are still out of order".
Question: Why does Kevin scream when he slaps the aftershave on his face? He didn't shave so he doesn't have any cuts, so it wouldn't burn at all.
Answer: Kevin did shave his face. His skin is sensitive from his first shave so the alcohol in the aftershave makes his face sting. Hence, the screaming.