I have attended many weddings, but I have never heard anyone say to the couple: Bon Mariage or Joyeux Mariage (at most, I wish them a happy wedding), of course, it is Fé weddings! There is no compliment, it is a sincere blessing, just like wishing someone a baby bb. Why don't you say, "Joyeux bébé/Bonne naissance? ! ! Ha ha. . . )