When your child turns 21, their YouTrip Family Child account will be suspended. To continue using YouTrip, they will need to close the Child account and sign up for a regular YouTrip account.
Please note that each user can only hold one YouTrip account at any time. This means your child will not be able to keep both a YouTrip Family Child account and a regular YouTrip Account simultaneously.
For more information on how to close an account, refer to this FAQ here.