I've vacationed with kids of that age and it's not worth the headaches and expense to take them anywhere specifically for them
They won't but you will. That was what was important to us. Seeing their faces (well, the older one, as you'll find out below) was worth it. Photos capture them forever.
Can't give you Tesla advice but I can give you Disney advice with kids. I went with a 2 year old and a...wait for it...5 week old....
and it was great. We had grandparent help but we could've probably done it ourselves if we just spread out the day. We went solo with our 1 year old the year before and had a blast.
Toys R Us sells stroller fans - they are amazing
Toys R Us also sells stroller rain covers. It rains almost daily like clockwork in Florida so this was helpful for those showers.
Every park has a baby care center which is air conditioned, has free water, is quiet, has changing tables, baby stuff that you might have forgotten for sale, and some books and tv playing for the older kids to stay occupied. Find these today. They will be a very welcomed site at noon in June in Florida. We would usually go back 3 or 4 times if we planned on staying the entire day at a park.
Most of our time spent at Disney was at the Magic Kingdom. They have the most kid friendly attractions, in my opinion. That being said, if you can it's worth staying at one of the close hotels (Contemporary/Bay Lake, Polynesian, Grand Floridian) We stayed at Bay Lake (next to Contemporary) and you can just walk to the Magic Kingdom. Great if you need to go back for a nap/meltdown.
All have great pools for an "off day" which helped us catch up and relax midway through our week.
Pay for the photo pass and take one at every opportunity. It's hard to find someone to take your pictures and even though the disney photogs will take photos with your camera it's great to have them online and have someone else deal with it all. It allowed me to leave my big DSLR in the hotel room.
I'm sure there's more I'll think of later.