hi, well as you haven't answerted any of the pertinent questions, then who knows? Perhaps you could just look at the link i provided and see for yourself if she fits the criteria?
Or perhaps she could look herself, or apply herself and see what happens?
in order to get carer allowance the person being cared for has to be in receipt of attendance allowance...... CA is an overlapping benefit if the carer is already in receipt of alternative benefits they may only get NI credit...if the son is under18 and you receive family allowance your credit is paid under home responsibilities protection ...not all benefits are overlappping though ...contact your local job centre plus office ..request an advisory interview.. I was an employment/benefit adviser for years and was only too happy to let clients know what they could get NOT to prevent claims being made...most of the staff the same...only a phone call to clarify things !