AN: This take place in the end/righ after season 6.
Rory eyed the giant petrified shellfish, which stared back with its empty eyes. And this was what Doctor called interesting.
"It's a Chalacwexin. They lived here in the seas about 7 000 years ago," River said coming at his side. "They were the biggest sea creatures of the planet. Actually, a lots like the whales on Earth."
"What happened to them?"
"When people from other planets came to live here, they set underwater fences preventing them from harming themselves with the infrastructure. The fences caused small but annoying nerve impulses if you touched them. The Chalacwexins didn't know how to react to the new obstacles and they ended up swimming against them until the impulses messed their nervous system and they all drowned. Not everything that lives has been blessed with an intelligence."
"Ah," he turned to look the other fossilised and preserved sea creatures in the exhibition hall. Doctor had brought them to a field trip to marvel the nature of Diuclite III, which was apparently deemed as the one of the most beautiful planets in the universe. Doctor had suggested a short hiking trip into the canyons a few hours from the capital. Rory had never warmed up for camping life, especially after the horrendous trip to the moors in Scotland when he was nine, but Amy had seemed so excited that he had volunteered to stay behind letting the others to enjoy the trip. For his surprise, River had suddenly offered to stay and keep him company and so Amy and Doctor had left at noon on their adventures and Rory and River had ended up spending their afternoon exploring the local Museum of Natural History.
"By the way, you wouldn't have to stay here with me. I would have been fine if you had liked to go with them," he said trying to sound nonchalant while moving to look a jar with what looked like purple jelly and some plankton in it.
"Maybe I wanted to have some quality time with my dad."
Rory glanced at her quickly before turning his eyes back to the jar. He still hadn't wrapped his mind around the whole being a father business. An awkward silence settled between them. Rory sifted his weight from a leg to another. "So… What's going on in your life recently?"
"The same old."
"Even with the Doctor?" he raised his brows. He could see her smile's reflection on the vitrine.
"Are you asking about my marriage?" she laughed a little.
"Maybe."
River didn't say anything for a moment. "It's like always."
"… I'm sorry."
River came to stand next to him at the vitrine. "Don't be. Relationships with time travellers are always complicated. Not everyone can have a perfect relationship like you and mom."
Rory snorted. "I don't think that applies to us."
"All the couples fight. It's completely normal, but doesn't lessen the value of the relationship, because in the end, you will always live together happily ever after."
Rory kept his eyes trained to the video of swimming jellyfishes trying to blink the blur away. He could just hope River was right.
AN: Some how this ended up becoming a kind of a bonding moment for Rory and River. Thanks for my sister, who helped me in doubt.