These picks span Hawaii's most water-centric family resorts, and the split reflects your actual options: go Disney-engineered and contained (Aulani), or chase serious aquatic infrastructure at a 5-star scale (Grand Wailea or Grand Hyatt Kauai). If you want your resort to BE the activity—not just a base camp for outings—these deliver. The trade-off is price and island choice; Kauai and the Big Island feel less crowded than Maui, but Maui's got the most pools per square foot. Pick based on whether you'd rather spend mornings at a snorkel lagoon or waterslide.