I don’t want to be that parent

My In laws are planning a trip for the family (Me hubby and our child Jensen who is 5 and our service dog ) to DisneyWorld. They Booked is plan tickets for 2020 and I just want to be prepared when it comes to flying with a 5 year old .

I was thinking maybe I should take a mini trip (45 minute flight) with Jensen to get him use to it?

I’m general Jensen is a pretty rock solid quiet kid . Too quiet sometimes but i think he’s pretty well behaved but I asked what to bring because this is his first flight ever.