Is it necessary for....

I'm leaving it up to the bridesmaids to decide what dress they want because I don't want to stress myself out over it. Each of them has different body types and wouldn't look good in the same thing. I wnt them to be comfortable in what they wear. Plus, its just not possible for me to be there with every single one of them to look at dresses (though i'll have some say before they order it).

The only one i'm probably going to shop with is MOH. I'm probably going to base the other dresses on what she decides. Once she finds a dress, i'll tell the girls what color and make to buy, the rest is up to them.

Not really. It's whatever you want.