We've taken our 13 yr old niece and our son's friend when he was 17 to Aruba. In both cases, we got parental consent forms from both parents, as well as medical and dental consent forms. We downloaded free forms from the internet, and they had to be filled out by the parents, signed, and notarized. We had all the papers at hand with their passports in case of inquiry.
For any international travel with children, I strongly recommend, where applicable, consent forms from a current or former spouse, or parents of unrelated children. Beyond border crossings, you would also need some of these documents in the event you had to find medical treatment for a child. International authorities are especially sensitive these days to spousal abductions and other hassles involving child custody, and although your chances of encountering a problem are slim, when you do run into one, it can be huge. An ounce of prevention...
You're welcome. Even if you're not asked for documentation, I think you'll feel better having it. At least for me, I feel a little nervous whenever I'm leaving the country, hoping I have everything in order.
A couple of tips, if you don't mind me adding, from our experience.
We might have allowed the boys more freedom then you will the girls, as they were a year older and, well, boys. We rented two cell phones, so that when they wanted to go over to the mall, grab a bite to eat at fast food, or to see their friends who were also on spring break, but at the resort next over, we were able to stay in contact.
We had copies of everything. I'll admit to being a little overboard about about paperwork, but I come by it honestly from organizing 50+ Boy Scouts to away summer camps for several years. I made sure the parents of the kids had photo copies of all of our passports, and I also carried photo copies of them, as well as the passports, but separately.
the minor child could also bring a credit card (parent's card with the child as authorized user)
in the event of a medical emergency, the parent's will be the one's that will be charged.
(not the guardians that are on the trip...the guardians will not have to look for reimbursement from the parents)
Our children have travelled many times without us to Aruba (meeting us there) while under the age of 18. Sometimes two siblings travelling together but one is underage. We have had proper travel documents done each time and they have been asked for the documents. Although this only happened once or twice it was good that they had them.
In Canada, with the exception of Quebec, there are no notories so we had a lawyer friend of ours prepare it for us. He made sure he had his "seal" on it. The letter included the child's routing plus the fact that he was joining us and traveling home with us too. Signed by both of us.
When I have traveled with minor children without DH, I got asked for my travel document twice.
When taking minor children with us, I also took parental letters from a lawyer plus a letter from parents allowing me to make any necessary medical decisions on their behalf. Got asked once for that too.
Multiple original copies were made and one was kept with lawyer (with his contact info), one with the minor child, one with each parent. Contact information was included for non travelling parent(s).