Hi, Meg! Fantasmic! is an outstanding nighttime spectacular. Although it is a huge ampitheatre seating thousands, it is filled to capacity for many of its showings, so plan on either the Fantasmic! Dining Experience OR plan to get into the queue 60 minutes prior to showtime.
There are some parts of the show that can be a bit dark and scary for your 4 year old, so you might want to have a small glow light or light sticks to keep all the "scary stuff" away! Each child is different: my daughter loved it at age 4, my son was scared of some of the scenes at that age. I do not feel it is so intense that you will need to leave during the show, but you might have your little mouseketeer sitting on your lap!
If you plan on doing the
Fantasmic! Dining Experience you definitely need an Advance Dining Reservation which can be made up to 180 days in advance online or by calling (407)WDW-DINE. You can do the "experience" with the Disney Dining Plan, but if you choose the Brown Derby for your dining location, this will count as 2 Table Service Credits. Hollywood & Vine and Mama Melrose's are both 1 Table Service Credit.
Remember, you can still see Fantasmic! without the special dining package, the "experience" just gives you a VIP voucher with special entry to the show.
Have fun planning your magical vacation for your 3 boys! Its sounds like so much fun. If you have any other questions, the moms panel is here to help! Just click
HERE so we can answer your question.