Ron was walking towards the carriages when he spotted Luna. While he knew she could be a little bit strange he didn't like that everyone picked on her so much. Walking up to her he noticed her petting something in front of the carriage. walking around the carriage he attempted to see what it was, but he saw nothing. Eventually Luna noticed him and said, "Hello Ron how are you this evening." "I'm good Luna. Don't take offence to this but what are you petting. I don't see anything." He waited for her to respond hoping he hadn't offended her.
Eventually Luna responded "Oh I'm just petting the thestrals. They're rather lovely creatures." Ron didn't know what she was talking about "What are thestrals Luna?" She took pity on him and explained it "Thestrals are black skeletal winged horses. They're what pulls the carriages. You can't see them because you haven't seen death yet. I have." Ron nodded somberly as he realized Luna witnessed her mother's death. He thought about how to lift her spirits and decided to just be friendly. "Say Luna do you want to ride with us. You can tell me more about the carriages and thestrals if you like." He offered. She agreed and they both got in with the others.
He noticed Hermione give them a strange look when they got in, but he ignored it. Luna and Ron spent the entire carriage ride talking about the carriages and thestrals just like he said. He found himself enjoying Lunas company and her facts about the thestrals. He almost snapped at Hermione when she nearly called her loony Lovegood. Yes, Luna was strange, but she wasn't a nut job.
(Time Skip)
The battle had finally ended, and Ron needed to leave before he broke down completely. As he exited the castle and made his way down, he spotted a familiar set of carriages and the small blonde in them. What was new to him was standing in front of the black Hogwarts carriages were black skeletal horses with wings. It's with startling realization that he was looking at an actual thestral. The heartbreak of why he could finally see them nearly made him collapse.
After a while of regaining his composure, he made his way inside the carriage lying across both seats. He felt as Luna laid the opposite way with her head on his stomach and grabbed his one hand in both of hers. Neither spoke as they laid there. They didn't have to the silence spoke more words than they could. They just laid there in silence together looking at the stars. This would be the first of many carriage dates spent looking at the stars. Even the day of their wedding they spent some time in a thestral drawn carriage. Just the two of them.
"There you have it kiddos. That's how your mum and me fell in love. Don't tell her but she had my heart on the very first ride in my third year." He said with a wink. Pandora and Fred giggled as their father finished the story. He picked both their children up and tucked them into bed before joining Luna in theirs. Life wasn't perfect but the Weasley-Lovegood family were taking it one day at a time and Ron wouldn't change one bit of it.