Who Hosts the Shower
According to tradition, a shower should not be thrown by the bride's immediate relatives, such as her mother, future mother-in-law, or sister, since it would appear that they were asking for gifts. The maid of honor or another good friend usually hosts, or several people, often bridesmaids, share the responsibility.
It is common for a bride to have more than one shower; when this happens, the hosts should consult one another about guest lists to avoid duplication. Showers are generally held from a couple of months to a couple of weeks before the wedding.
Regardless of who throws the shower, the host should be on hand -- alongside the bride -- to meet guests as they enter the party.
Read more at Marthastewartweddings.com: Wedding Events Etiquette -- Martha Stewart Weddings