Is this a good water park for young children??3-4 y.o??

They have a area for young children.

Both water parks have little kids areas. Plenty of cast members ( life guards) in these areas.

Yes he was going to make sure you get there early enough so you can get the shade and stay down there the water pool

Yes

i was just there with my 5 yr old. she loved it. they have an entire section of the park specifically for that age.

Yes, they have a children's area. Blizzard Beach also has one, too.