Originally Posted by Sapphire at Dawn
I agree with Hopeful_song in that it wouldn't be OOC for Lily to go and ask Petunia personally, but that it would be OOC for Petunia to change her mind and attend. Something I'd like to add is that the Potter's wedding was a very secret and hushed up affair, so would Petunia have known about it or been invited? I'm leaning towards the idea that she would have known as she and Vernon are Muggles and not connected in any way to the wizarding world so are unlikely to be a threat to their security, but it does depend on how you want to play it and what is happening in your story. If Lily and James are in serious danger from the Death Eaters or Voldemort, would they be allowed to have anyone other than members of the Order at their wedding, people who can be trusted to keep the secret?