Hi all, I'm taking both of my nieces to Europe with me this summer. One niece is 24 the other will be 17. My sister (the mother of the 17 year old) will take her to Italy and then to Paris. My older niece and I will meet them in Paris then my sister will fly home a day or two later. My plan is to take them through Belgium, Netherlands, Germany and possibly Czech Republic too. Does anyone know what (if any) documentation we would need for my 17 year old niece to travel with me since I'm not her legal guardian?
Thanks.