i have a question about my icloud password can u help?

I got this ipad mini 2 from a cousin and the didnt want it anymore but my problem is that he cant remember his password to the icloud account and i am trying t remove it and add mine on there but we dont know the password and he no longer has access to the email. How do i remove the icloud account on my ipad without having to factory reset the ipad. Please help me

Thank you