Includoing the little ones.
In several posts you have expressed a concern if there is enough to do for the children. On arrival at each park, visit the visitor centre and enroll the the children in the junior ranger program. The program is age appropriate. The children will have lots to do and explore to earn their rewards, and will have learned much about the park, its history and its future. No doubt you will do it with the three year old.
But don't sell yourself short by going to the West Rim. As mentioned above, it is NOT the national park, not anywhere near as magnificent, and as well as their exhorbitant prices, you will be forbidden to take a camera with you. Its just not worth it!
At Sequoia NP, besides the junior ranger program, there are huge fallen trees the children can climb over, and even one they can walk through. The latter being right by the parking area for disabled. Your children won't run out of things to do.
Lifey