Merlin had not expected Arthur to remember. Of course he hadn't. It wasn't like he had ever told him. Merlin probably wouldn't have remembered Arthur's birthday either if there hadn't been a big bloody feast every year for the occasion. So when Merlin woke Arthur with a cheerful “Good morning!”, and Arthur's only response was his usual incomprehensible grunt, glaring at Merlin as if it was his fault that the sun kept rising and Arthur had duties, Merlin absolutely wasn't disappointed. He had, after all, expected nothing else.
''I brought your breakfast, Sire!'' Merlin said, opening the shutters to let in the sunlight. ''Looks like it'll be a beautiful day.''
''I'm sure it will be, Merlin,'' Arthur said with an eye-roll before he climbed out of bed yawning and ruffling his own hair so that it stuck out in every direction. He took the britches Merlin was holding out for him, only to shove them back a second later. ''Not these. We're going hunting today.''
Merlin's face fell, and he quickly turned away to hide his scowl. Awesome. Just what he really wanted to do on his birthday: to trudge behind Arthur through the undergrowth, carrying all his stuff and being hissed at and called an idiot every three seconds because strangely enough that didn't make Merlin anymore light-footed.
''Of course we do,'' he mumbled with a sigh, but Arthur didn't seem to notice.
They had been riding for a good half hour already when Arthur suddenly stopped, turning around to Merlin, who was riding behind him, with a frown.
''Alright, what's wrong?'' he asked.
Merlin looked around, trying not to meet Arthur's eyes. ''Nothing.''
''Why should there be anything wrong?'' Merlin asked defensively. It wasn't as if Arthur could read his mind or anything.
Arthur, though, looked at him as if he was the worst kind of idiot, which only made Merlin bristle even more inside.
''You're silent,'' Arthur said.
Merlin raised his eyebrows.
''Merlin. Normally I'd have told you to shut up seven times already since we left the castle because your mouth doesn't bloody stop. Ever.''
''I thought you'd like it better that way.''
''Well... stop thinking then!'' Arthur snapped in obvious exasperation.
Merlin frowned at him dubiously, but kicked his horse to ride up to Arthur's side. It was always best to try to indulge His Royal Highness, or Merlin would only make this even harder on himself.
''So...'' he said with a fake cheerful smile as soon as he had come to a stop next to Arthur. ''Where are we going?''
It was Arthur who scowled at him now. Really, there was no pleasing the prince when he was in a mood.
''To the pond.''
''I thought you wanted to hunt?''
''Well, I changed my mind, Merlin.''
''Wha-... I've been lugging about all your stuff!'' Merlin groused indignantly.
''You're sitting on a horse, Merlin. It's not like you carried my crossbow yourself all the way, so... stop complaining! Okay?''
Merlin bit back an angry retort, and followed Arthur when he urged his horse forwards.
When they reached the pond, they tethered the horses to a nearby tree.
''So...'' Merlin looked at Arthur expectantly. ''What now?''
''The weather has been nice for a while, so I thought a swim might be a good idea,'' Arthur said, starting to pull of his tunic.
He took down the blanket Arthur had strangely enough insisted he'd bring on their hunting trip, as well as their provisions, setting them out under the shade of a birch tree.
''What are you waiting for, Merlin?'' Arthur called a little while later, when Merlin stood around, next to the blanket, feeling silly and useless.
''What?'' Merlin shouted back. He had no idea what it was he'd supposedly forgotten now.
Arthur, standing in the pond with the water up to his waist, rolled his eyes at him. ''Well get off your clothes and get in the water! Don't be such a girl, it isn't even cold!''
''You want me to-?''
''Well, that's what we're here for, isn't it?''
Merlin very nearly pointed out that he had no idea what they were here for, but thought it more prudent to comply. He hastily kicked off his boots and slipped out of his tunic and trousers, and then gingerly waded into the water where a tousled and grinning Arthur waited for him. It was such an unusual look on Arthur that Merlin couldn't help but smile back.
''What now?'' Merlin asked when he was next to Arthur in the deep water.
Arthur shook his head as if he couldn't believe Merlin had asked this, put one of his broad hands on top of Merlin's head, and simply pushed him under the water. When Merlin came back up, spluttering and spitting out half of the ponds contains, Arthur said with a smirk, ''Now you relax and enjoy yourself.''
Merlin glared at Arthur, but then thought better of it and dunked the blond prat with a broad smile that stayed right where it was, even when Arthur broke through the surface with an indignant scowl, shaking his hair out of his face.
''Merlin!'' he exclaimed, rubbing at his eyes and glaring at Merlin, but with the corners of his mouth twitching suspiciously. ''You can't just dunk the crown prince!''
''Says who?'' Merlin retorted, and there was nothing fake about his smile now.
''Oh, you just wait!'' Arthur threatened, and then the fight was on.
Of course Arthur being Arthur, and also a trained knight, got the better of Merlin who had no way to use the single weapon who'd have granted him a rare victory over his friend and master. But it wasn't important, Merlin thought as he waded out of the pond a while later, shaking with laughter and wiping the water out of his eyes.
He let himself fall down onto the blanket, stretching out in the flickering sunlight that filtered through the leaves.
''So what's the purpose of this whole trip?'' he asked Arthur when he slumped down next to him.
''You still don't know that?'' Arthur asked. ''I know you're a bit of an idiot, but I thought even you would remember your birthday.''
Merlin froze, his breath catching in his throat for a moment. ''You remembered?'' he croaked.
''Of course I remembered,'' Arthur said, nudging Merlin in the ribs. ''It's not like I'm an idiot!''
''Just bloody take it!'' Arthur growled, later that day, when they were back at the citadel.
''But what am I going to do with it?'' Merlin asked, looking down at the... thing in his hands with a frown.
''I don't know, Merlin,'' Arthur said, eyebrows raised up so high they almost vanished under the blond hair falling into his face. ''What does one normally do with a puppy?''
''But why are you giving it to me?'' Merlin whined.
Arthur shrugged. ''It kind of reminded me of you.''
''It was the weakest of the litter. The others kept pushing him away.''
''Oh my god. You gave me the runt. Because you knew I would feed him and care for him and you couldn't watch the poor little baby starve, isn't it?''
''Don't be ridiculous, Merlin!'' Arthur scoffed. ''I just... I thought you would like him. As a present. For your birthday.''
Arthur looked around Merlin's room awkwardly, and Merlin would not have been able to keep the smile off his face if he had got hard coin for it.
''I love him,'' he said, grinning like a loon. ''I think I will call him Arthur.''