Please help me adjust my attitude

Yesterday we had a get together with FI's extended family, and two of his cousins announced they are expecting!! I was super happy for them until they told me their due dates...May 20th and June 14th. Our wedding is June 1st. I'm so extremely disappointed that they won't be able to come, the cousin who's due on May 20th is my favorite relative of FI's, and I was really looking forward to celebrating with her.
Should I consider trying to move our wedding date so they could attend? We've already put down deposits for the ceremony and reception venues and our photographer. It will be a two hour drive for both of them and I don't expect them to do any traveling so close to their due dates.
Here's the Bridezilla part: I'm really worried that his family won't even care about our wedding, and will just be focused on being excited about the impending babies...help me snap out of it!!
Re: Family Announcements (aka I'm a Bridezilla)
Babies trump weddings all the time. It's no big deal. The new mom and mom-to-be may or may not attend and that is true not matter what day of the year you get married. Don't change anything and keep planning the wedding you have been planning.
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