Using term their vs our in a marriage invitation letter

I recently happened to see an invitation letter as follows

Mrs X and Mr Y

cordially invite your esteemed presence and blessings with your family on the auspicious occasion of the marriage of their daughter

K

Grand D/o so and so

with

L

On date at location

Marriage party leaves at time.

---

With Best Compliments from Friends and Relatives

Is the usage their correct in this context, or is our correct?

My understanding is if this has been called on behalf of someone else the usage of their is correct. But as this is called on the behalf of the parent themselves it should be our. Or does this have any relationship with the line With Best Compliments from Friends and Relatives.

Solution 1:

"Their" fits the "Mrs. X and Mr. Y" at the beginning. I would think that if the invitation begins in the 3rd person, it would be proper to use 3rd person pronouns, as in "They (Mrs. X and Mr. Y) invite you to their daughter's wedding"... Although some other parts of the invitation sound a little off. In any case "their" seems perfectly justified.