Have a chat with the kids and get them used to the idea that they will be “hanging out” with me. Refer to me as Ains, not “the photographer”, this way using my name humanises me and makes it less intimidating to be meeting a total stranger. Let them know that we want to photograph them as naturally as possible so there will be heaps of opportunity to adventure around and have fun! The best way to keep the session fun is be positive, keep the tone and talk around the photo session fun and exciting. Letting the kids know they are going to the beach or a park with you guys to have their photo taken with their family, how long it will take and how important it is to document, will help get them in the right mindset for the session.
Setting expectations will help the children do their best.