Student Finance Dependent Evidence

So I’ve sent my application for student finance, and it’s going through the process right now. I just received a letter that says that my mum would need to send evidence of how my siblings are dependent on my mum over the age of 18. I have two other siblings who are both not in full time education. My sister is going back to college this year and my brother has finished university the previous year. In the letter it doesn’t state what type of evidence?


What type of evidence do I need to send?

My brother is a career for my mum and he gets universal credit, Where as my sister is working full time until she starts studying again.