"This is our family gathering, what are the Wilson's doing here? If you had issues with inviting the guest, you should have let someone else do it." Dad spoke calmly. It was evident he was trying to contain the rage burning in him, I guess he wasn't having it.
I could understand his anger, I would do the same too if my child was treated the same way.
"It's Hazel's party David, and these people are family to her so why not invite them?" Grandma said calmly like someone who forgot both families had issues.
"Dinner's served." The butler announced and Grandma clapped. "That's great, please everyone, ignore the little drama and let's head over to the table."