Ok everyone, I need some clarity here. I just ordered 200 thank you cards thinking that I could use them for the Engagement Party, Bridal Shower, and Wedding. My FMIL just told me that I should do a different card design for each occasion. The thank you card is actually blank with a simple design. I'm going to write a personal message on each card for each person. FMIL thinks that if the card is the same (design), it will seem insincere. I didn't even realize that cards need to be different in design and this thank you card is part of the design I'm using for my invitations and save the dates.
So what is the proper etiquette here? Should I throw out 200 cards now?