This time Opal stepped in and when the two were out of earshot, she went ballistic on Buzz for pushing another son away from himself. She might've been angry at Rick, but she missed him greatly and couldn't believe her husband was willing to lose Buck over prejudice.
Buzz tried to explain to her why aliens have been a problem in Stangetown for decades and why he joined the army to protect the town from green people taking over, but she was not having any of it. If he was able to move on from his hate towards the Smiths, he should be able to accept Buck's boyfriend as well.
If there was anything Buzz was helpless against, it was angry women and Opal was able to turn this retired military man into a mouse. She warned her husband he will end up all alone if he doesn't stop harassing everyone around him.
Opal: You will be a grandpa again, for Watcher's sake! And you will love the baby - green or not!
Opal: You WILL apologize to the boys and make sure they stay here! Is that clear?