You have created a profile for one child & now you need to create a separate profile for your other child/children. Simply log into the existing account, on the left-hand side, you will see a red box that says 'new' select this and fill in the child's details.
Once you enter through the details of your child your child's page will then be activated!
Hot Tip! You can then navigate between the children's accounts by clicking on their name on the bar on the left-hand side.