When a very pregnant Mia realizes her condition will prevent her from participating in many of the wedding day festivities, she and Casey decide to postpone the ceremony until after the baby is born, and then set out to recoup their deposits. Meanwhile, Ben decides to have some fun with Joel when he discovers the father of the bride is unable to stop shedding tears while preparing his wedding day toast to his little girl.

Mia goes into labor, only to decide that she and Casey should bring their baby into the world as a married couple. So Casey and Ben zip over to City Hall for a license, while Maddie scrambles to find an authorized official to perform the ceremony. Meanwhile, the grandparents-to-be scour the gift shop for the traditional something old, something new, something borrowed and something blue.