Do I need to provide proof that I'm in receipt of Child Benefit?

As part of the application we will ask you for your Child Benefit Reference number. You can find your Child Benefit reference number on any letters from HMRC about your child
benefit, or from your bank statement. If you are getting the number from your bank
statement, then we need the first 8 numbers only. You’ll have to show us confirmation of where the payment is currently made (e.g. bank statement, Post Office Card statement).