If at all you do decide to go ahead with replying would go along with FY's advice as from my experience too its always about them...
The other day H accepts a social invitation only because he is repeatedly told to him that he has to be there and that there is no way he can avoid coming there..
So the decision to go did not stem from the fact that it would make the inviter happy and that it was a big day for him , it was accepted only because H was made to feel important and that his presence was critical..Arrrgh..my 2 cents
Take care ,
hoper me-40,H41 M-15 S-6 Looks like MLC,living together