Mother's old passport name in Father's passport's spouse column

[ank14]

Hello, 
I am applying for my parent's B1/B2 visa to attend my graduation ceremony in US.
My mother's new passport is 'GEETA' whereas old passport 'GITA'. My Father's passport spouse has 'GITA'. Where as on my Passport, my mother name is 'GEETA'.

Will this create any problem in the interview for both of them in one slot? What supporting document should I have to show that my Father's spouse and my mother are same? Please help.