Thanks for all the feedback. The parents chalked it up to happening on the drive over. They haven't given me any reason to not trust them in the past, so I'll take their word for it and leave well enough alone. Hopefully this gentle reminder will prevent it from happening in the future. Although, I can tell the one parent is upset based on the email response I received. Hopefully the emotion goes away and we can move forward in a positive way, like we have been for months now.