Help late SFE application Proof of income

I am applying late due to personal circumstance(injury and sickness). I have applied for more than the standard maintenance allowance

The sponsor I am dependant on (my mother) was unemployed for the tax year 2021/22 so zero income and was on universal credit which is non taxable income, so I know I am eligible but what proof do I upload on my mother's sfe sponsor account??

Since there is no income and she was on UC which is tax free

Thank you.

Thank you for replying.

Yes, she will declare zero income but do we have to upload any evidence or document or will they ask for any evidence?