husband leaving town before due date

My husband's little brother is graduating soon and lives out of state. My husband is planning on visiting him from June 7-16th to spend time with family and attend the graduation. 
However, my due date is on the 16th!!! I am furious. What if the baby comes early? I feel like the birth of your first child is more important than a high school graduation.
I rather him have to skype the graduation ceremony than Skype our child's birth. Should I be annoyed by this? Or am I overthinking it? 
I just want a second opinion.