I remember when my friend had given us a dozen eggs (they are always super fresh from within 24 hours, most of the time less than that) & my husband was making a “Big” breakfast. When he cracked the eggs, 2 of them had double yolks. We were amazed! 
We haven’t seen them since then. I should ask him how often he’s had it happen to him before. I feel like there have been other times in the last 20 years that it’s happened. I don’t remember any before that though.
I believe @BryWisteria had an experience with double yolks as well 1 morning! 
What the Yolk!?