When Jim/Sam is done showing Aiden the magic trick, he surprises him with a magic kit. Seconds later, Melinda asks when Aiden became interested in magic. Jim replies that another boy learned some and Aiden felt left out so he took him to pick up the magic kit.
How could he surprise Aiden with the kit, if he took Aiden with him to pick it out.
About nine minutes in when we briefly see a corpse in a hospital, the throat can be seen moving quickly.