Wearing white to a wedding is a faux pas. Unless the bride tells you to wear white, then you absolutely must. On a popular Reddit thread in the Am I the A**hole Subreddit, a woman wears white to her sister's wedding and receives a lot of backlash.
AITA For wearing a White Dress to my Sister’s Wedding?
I (28F) was invited to my sister’s (32F) wedding on October 4th, 2022. For months my sister planned for her wedding, and about four months before the wedding, she let us know her maid of honor, bridesmaids, and all other things to do with guest roles, etc. Well, I was one of her bridesmaids.
My sister didn’t want to buy all of the bridesmaid's dresses as she wanted us to contrast and feel comfortable in our dresses, but one thing she let us know was that the bridesmaids were to wear WHITE dresses.