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A loud knocking at his bedroom door woke Mycroft with a start and he sat bolt-upright, every muscle tensed. He relaxed and fell back to his pillows with a groan as he saw Sherlock slick his head round the door.
"What is it Sherlock? It's barely daybreak, go back to sleep."
"You said you'd teach me to fly." Of course that's what his baby brother wanted. He'd only started shifting a couple of months ago, and had been badgering him ever since. Why did the shifter gene have to skip a generation in both of his parents? Then Sherlock could have gone and bothered them instead.
"Later, Sherlock. Just let me sleep."
"But you promised!" And there it was; that wide-eyed, trembling lip, kicked-puppy expression universally known instinctively by every child on the planet. Mycroft cursed under his breath. He'd been at secondary school long enough to pick up a few choice words from the older students, partly because he had a few classes with them.
"And I will, this afternoon. Now will you please leave me alone?" Having gotten the answer he was after, Sherlock grinned and made his way back to bed, but not before Mycroft caught a glimpse of reddish-brown as Sherlock's tail; still fairly short and stubby, grew out unbidden in the 7-year old boy's excitement.
Sherlock did not go back to sleep - he was too excited. Today he would be learning how to fly, and he was already imagining himself soaring over their garden with the golden eagle that was his brother at his side, scale to feather. Instead he finished the shift and looked at himself in the mirror. Despite his young age, as a dragon he was already pretty big, almost as big as the lions he had seen when Mummy had taken the two of them to the zoo. He stretched out his wings, feeling the pull of muscle and marvelling at how the early morning light shone through the membrane that would in a few hours allow him to fly.
Two hours after lunch he was finally outside in the large field behind their house that served as a garden, staying well clear of his father's beehives. Sherlock was so excited he practically vibrated into his scales. Mycroft was still human, and stood on a small box so he could reach his brother's wing.
"Now Sherlock, it may be hard to start with, your muscles aren't used to flying yet so you'll need to build them up." He gently guided Sherlock's wing into a diagonal swoop, demonstrating how Sherlock would have to move them "And then hold them like this to glide, you can make your own updrafts to save energy." He held the wing steady, the back slightly lower than the front. "Use your tail like a rudder to help steer, and try not to crash into anything; you'll heal fast but if you break anything we'll both get in trouble. Have you got all that?"
Sherlock was already familiar with the theory after spending hours at a time pouring over books of avian anatomy, but he still nodded vigorously, and then took off at a run, beating his wings for all he was worth. For a moment he felt his feet leave the ground, but he didn't stay airborne for long, and soon came crashing down. But Sherlock had always been stubborn, so again and again he ran the length of the garden, occasionally gaining a couple of feet of altitude.
They had been at it for most of the afternoon until finally, with a triumphant roar, Sherlock became airborne one more, and stayed up. Flush with success he beat his wings harder, climbing higher with every stroke, shooting forth the occasional burst of fire to help keep him aloft. Mycroft gave an uncharacteristic shout of joy, and the next moment he was flying alongside his brother. He tried to race a small aeroplane, but before he could get close enough Mycroft nipped at his shoulder and they turned back for home.
Sherlock spend most of his free time that summer in the air, becoming more agile every day until he was swooping through the skies with the various birds that had made the Holmes' garden their home as he learnt the small tricks that only wild birds knew. He even once spent the afternoon with a falcon, learning how to dive in almost a free-fall until he was giddy from the adrenaline rush. His mother had found him that evening lying on his back in the garden laughing from the thrill.
Sherlock stood on the roof of 221 Baker Street, John at his side. Find foot and hand holds in the dents made by Sherlock's muscles until he was settled between the pair of huge leathery wings, arms wrapped around the scaly neck in front of him. Sherlock spread his wings and flew; the feeling of the rush of wind over his hide and under his wings made all the more exhilarating by the whoops of joy in his ears.