For most major cruise lines in 2026, the minimum age to participate in the standard, supervised "Kids Club" programs is 3 years old, and the child must be completely potty-trained (no pull-ups allowed). Lines like Royal Caribbean (Adventure Ocean), Carnival (Camp Ocean), and Disney Cruise Line (Oceaneer Club) generally follow this age-3 rule for their complimentary programs. However, many lines have expanded their high-fidelity family offerings to include "Nurseries" or "Baby Clubs" for infants and toddlers. For example, MSC Cruises and Disney offer nursery services for children as young as 6 months (or 12 months on some longer sailings) for an hourly fee. Royal Caribbean also offers a "Royal Babies & Tots" nursery for the under-3 crowd. While the standard "drop-off" club is usually for ages 3-17, these specialized nurseries allow parents of very young children to have supervised child care, provided they book a slot in advance. Always check the specific ship’s deck plan, as older or smaller ships may have more limited facilities for the youngest passengers.