I meant to edit but ended up deleting my message. I was saying they couldn't get an onboard credit, even if you booked for them while on a cruise. However, if they are going on a cruise with you in the future, you can book a cabin in your name and another cabin in your wife's name. Your cabin would have someone else with you, and your wife would have your daughter in her cabin. You just change the name in the cabins at the pier on the day of the cruise.