My mother wants to visit USA. She is going to apply for visitors visa. She is a widow and she lives in India with my two siblings, who are still studying. Her source of income is the income from our agriculture farms, rent she gets from tenants living at her home, pension and Fixed Deposit. She also owns 2 houses. When she'll visit US, she is going to stay at my place but she is sponsoring her and my siblings visit on her own. As my siblings are still studying and my mom has property of her own in India, it proofs she is definitely not going to stay in USA. What documents she is required at the time of visa interview?