Kimberly Said:

How do I write a letter of invitation for my future mother in law to visit us in the US?

We Answered:

There's no legal requirement for a letter of invitation. So, if you still want to write one, just say what you feel. send it to her and have her take it with her. certainly, you should mention the marriage and include the invitation if you like.

Mitchell Said:

How Do I write a Visa invitation Letter to my parents so they can visit me and their grandchild’s in the US?

We Answered:

You have some specific questions which probably can be better answered by other posters.

However, the reason I am writing is that you mentioned responsiblity for their tickets and their expenses. That is a good start, but Immigrations and Customs Enforcement is primarily concerned that your parents will return home after their Visa expires, and not overstay in the US.

You or your parents need to prove (during their visa appointment) that your parents have significant assets in their home country (house, rental property, significant job/significant job position) that would incentivize them to return to their country. Since you haven't really commented on that in the posting, I leave it to you to determine how to best demonstrate that to the consular official.

Good luck.