Crystal Cruises announced guests can bring a kid 17 or under free if they book select fall sailings this month. For children to sail free, they must be accompanied by two full-fare adults.

Family groups of 6 or more can qualify for $400 on board spending credit, as well as a $500 credit towards a family photo, Crystal Private Adventure and other benefits offered with the “Crystal Family Memories” program of the line.

The offer applies to seven cruises aboard Crystal Symphony and ten sailings on Crystal Serenity between September 1 and December 31 and is set to expire at the end of April. 

The sailings range from several 7-day Caribbean or Canada & New England sailings up to a 15-day holiday sailing to Rio de Janeiro from San Juan.

Crystal said its luxury ships included purpose-built Waves and Fantasia kids' and teens’ facilities, as well as top video games, toys and events that would add appeal for children.