No. It is not a requirement that the children_sign sign the cards before the application is submitted but the Leader must ensure they are signed before travel. However, all cards MUST be signed by the Leader prior to submission.
24-hour Passport Adviceline: 0300 222 0000 (see terms and conditions). Calls made to 0300 numbers from landlines and mobile phones are charged to customers at their network provider's national rate. Live operators are available to assist with your enquiry 24 hours a day.