If you have forgotten your password you will need to reset it. To reset your password open your parent app, on the sign-in page press "forgot password".
You will receive a four digit code via SMS (that you will need to use when you reset the password) and an e-mail with a password reset link. Open your e-mail, click the reset password link. In the new reset password page, enter the four digit code you received via SMS, and your new password.
Your password is now reset.