Welcome to the Disney Parks Moms Panel Kate ~
It sounds like you are planning a very exciting vacation and will create some incredible memories as a family.
I am a huge fan of Disney tours and we absolutely LOVED the
Wild Africa Trek. I did it with my youngest son who was 8 years old at the time. There was nothing that spoiled the magic . . . in fact it created more for my son. Most of the backstage areas you visit seemed to be created especially for this tour. They are either on the safari or near the safari and do not involve any character areas. I have been on a lot of tours and I would not consider any places on the Wild Africa Trek true backstage areas. Disney keeps that in mind and has a policy that Guests must be at least 16 years of age to visit those areas.
A lot of the walking during the Wild Africa Trek is off the beaten path. There are some stairs to navigate as you make your way up and down to cross over the shaky rope bridge. My son did not have any problems navigating any of it. He was the only kid on our tour and the tour guides were great with him. They made him feel really special. Everyone I have talked to that has taken their kids on the Wild Africa Trek loved it. It is a great way to explore your Disney Wildlife Side.
Please feel free to visit again with any other questions. We are hEAR for you!
Wishing you minnie magical memories :-) Allison V.