Visitor VISA for parents - I am a student

[campuschill]

Hello,
My parents are planning to visit me and they are going for VISA interview soon. I am a student married and have a baby. However my wife just got her visa status changed to H1-B and started to work very recently. My parents are trying to show it as a self supported trip, is this the right method to pursue. if so then do i need to send an affidavit of support or is there anything else i have to send other than the invitation.

If this is not the right method, what do you guys suggest.

Thanks

[Murali]

If they are sponsoring themself then there is no need for affidavit of support.
However a letter of invitation stating some travel plan would help or may be useful.