On Royal Caribbean, you can check in for other people as long as they are part of your linked reservation or in the same stateroom. Using the Royal Caribbean app, the primary guest can enter the passport details, take the "security photos," and link credit card information for everyone in the group. This is highly recommended to expedite the boarding process, as it allows the entire party to receive a "SetSail Pass" simultaneously. However, there are strict limits: you cannot physically "check in" for a person who is not present at the actual cruise terminal. Each individual must be physically screened by port security and have their identity verified by an agent or biometric scanner before they are allowed to board the ship. Furthermore, if you are checking in a minor for whom you are not the legal guardian, you must have the appropriate notarized "Parental Consent" forms ready to show the terminal agents, as the digital check-in does not replace the legal requirement for physical documentation in those specific cases.