ARIVERA6:

It is that bride's special day and the focus is supposed to be on her!

Uhh. The bride's day? Are you sure you're not thinking of a beauty pageant? Most weddings involve at least one other person. Also, the point of the wedding event, as opposed to the marriage ceremony, is to share the experience with family and friends.

ARIVERA6:

Not her flashy mother-in-law. Give me a break. She's not being spoiled, it's just proper etiquette to dress appropriately and not like some tramp to a wedding, especially your son and his future wife!

Maybe the MiL should not have picked that dress. But that's not the question. The question is whether the bride should try to get her not to wear it. The answer, is "NO". She should keep her mouth shut. It will be good practice, which she clearly needs.