Hi Theresa,
Both of Disney's water parks have areas specifically designed for toddlers and preschoolers. If you go to Blizzard Beach, I think you'll find that the unique and clever theme of a melting ski resort is quite charming. You'll want to head to Tike's Peak with your children in this park. Here they have cute slides, forts shaped like igloos, and a wading pool. My favorite activity at Blizzard Beach for families with small children is to hop on an inner tube while riding Cross-Country Creek. Your young son or daughter could rest comfortably on your lap as the two of you enjoy the soothing ride and beautiful scenery.
If you choose Typhoon Lagoon instead, then head for Ketchakiddee Creek. Here your children will find geysers, waterspouts, slides, a raft ride, and a grotto with a small waterfall. This area is restricted to kids under 48 inches tall. Castaway Creek is similar to Blizzard Beach's Cross-Country Creek, in that you and your child could ride this gentle inner tube ride together throughout the park. This park is themed like a tropical island.
You can't really go wrong with either park. I suggest you show the
gorgeous photographs of both parks to your family and ask them which they'd prefer to visit.
Have fun splashing around the Disney water parks!
Jill