With a 2-, 3-, and 4-year-old, you need an all-inclusive where toddlers don't get lost in the shuffle. Hyatt Ziva Cancun nails this—it's family-only (meaning no spring-breakers), has a real waterpark, and runs one of the Caribbean's best kids clubs designed for your exact ages. Moon Palace is the scale play if you want more restaurants and amenities; it's bigger and busier but equally solid for young kids. Both have the infrastructure to keep toddlers engaged without parents burning out. Club Med's mid-renovation closure of its main pool makes it a skip right now.