I’m going on vacation to Punta Cana with my family and I’m taking 2 of my daughter’s friend with us. Do their parents need to get any kind of document authorizing their daughters to travel with us?

For Amber alerts purposes you should carry a notorized letter giving you (specific person) permission from both parents for each minor child thru a lawyer or notary public to make it legal and valid. Carry it with your travel documents at all times, will come in handy (specially when re-entering the Estates.) Happy travels!.

If you travel with the girls back and forth you don't need any kind of authorization from the girls parents.