universal credit is ruining me

Your mum should get Child Benefit for all 4 of you. It's Child Tax Credit and Universal Credit that is limited to the first 2 children. She would lose Child Benefit for you if you aren't in education or training under the age of 20.

yeh she is for 2 but my since me and my sister are over 16 she had to let them know that we are in colloge to continue child benefit. but I want to know if they will do reduction in parts such as what pays for rent and expect me to support my mum.