When applying for Dependants Allowance for the first time you are asked to provide proof of Child Benefit for all dependent children.
If the child is over 16 we require proof that they are still in full-time education and a Child Benefit letter for each year of your course.
For children who are up to school leaving age you do not need to provide proof of Child Benefit when reapplying in the subsequent years of your course. You only need to provide proof of Child Benefit again if you have a shared living arrangement for the children.