Visitor visa for parents - name confusion

[JyothsnaParikshith]

Hello ,
I want to sponsor my parenst on visiting visa. My mothers name is different in my fathers passport and also in mine .
In her passport it is like LastName Lakshmi MiddleName
In my fathers it is like Laxmi MiddleName
and in my passport it is like LastName Lakshmi

Lakshmi is her first name but mispelled & last name missing in my fathers passport and in my passport her middle name is missing.
Some one told me that I can mention her other names in DS156 form . But I am confused if non usage of middle name and last name in some places be mentioned in DS156?
Anyone's help in this regard is greatly appreciated.

Thanks in advance.