For those times that we actually pay for our flights (yes, we do this at times), I make sure that everyone in my family is getting credit for their flights. Also, my kids are getting old enough where they will start to travel without us. Read here about Daniel’s point earning trip to Turks and Caicos. Most airlines do not have a minimum age to become a member of their frequent flier programs. So why shouldn’t the kids start earning points as well!
One problem that you may run into when your kids have ff accounts, is the miles expiring due to the lack of activity in the accounts. Read here about tips to avoid mileage expiration.