My name is ***** ***** I am a NSW Solicitor. Thank you for your question, and will do my best to assist you with your question. Please understand this is not legal advise Please understand this is not legal advise but a guide to assist you.
You should have the parents consent and something from them signed they agree and allow you to have your grandson would be helpful.
It would be best if it was a document signed before a Justice of the Peace or a Solicitor.
You should contact the cruise ship and they will also tell you what other documents they require.
But at the very least you will need the authority from the parents.
I hope this makes sense and is of assistance.
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