The surefire way to make sure this does NOT happen is to micromanage your BMs. "Did you buy the dress yet? Did you buy the dress yet? I called the shop and they said you haven't ordered yet. When are you going to buy it?" Especially if you want them to buy it by a deadline YOU, not the shop, came up with.
Yes, in a perfect world everyone would do things on our schedule. But that doesn't happen in life, it won't change for your wedding. Just let go. If your BM is a last-minute kind of person, she will probably buy her dress last minute.
While stressing over this to make sure it gets done far in advance may make you feel more in control, it almost always backfires and/or creates bad feelings. Trust your best friends and family not to leave you hanging. You picked them because they're there for you when you need them the most. So why would they suddenly choose your wedding to screw you over? Think about it.
Courtesy of megk8oz

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