"Char'ie!" George said urgently. "Char'ie!"
Charlie sighed and looked up from the Quidditch annual he was reading. The two boys were upstairs in their parents' bedroom, avoiding the monumental row that was going on downstairs. Percy had managed to fall into a sea of mud in the orchard, while Bill was supposed to be watching him and the twins, and Bill's attempts to rescue him had resulted in both of them – and somehow one of the twins as well – becoming completely plastered in thick sticky mud. Their mother was not impressed, and was letting Bill have the sharp edge of her tongue. Her shouting, Percy's crying, Bill's increasingly frantic pleas that it really wasn't his fault and baby Ron's yells meant that the kitchen was not a pleasant place to be right now. Charlie and the unmuddy twin had beaten a hasty retreat upstairs to get away from the noise.
"What?" Charlie demanded now. "I'm busy, George."
"Not George, me Fred," the younger boy insisted automatically, but Charlie was not to be fooled.
"No, you're not," he replied, shaking his head and sounding as stern as a seven-year-old could. "You're George. You don't get me that easily. You should have learnt that by now. What's up?"
"Fred," his brother said, pointing at the long mirror on the wardrobe door.
Charlie sighed again, shut his book reluctantly, and stood up and walked over to where his brother was standing in front of the mirror.
"I told you," he said. "I know who you are. You're George, not Fred. You might get Mummy and Daddy and Bill and Perce like that, but you don't fool me."
It was perfectly true. At two, the twins had recently discovered the fun to be had by pretending to be each other, and had become very adept in a very short time at tricking most of their family. It infuriated their mother and Bill, amused their father, and confused poor little Percy. But they had never yet managed to fool Charlie, and they both knew it. Charlie didn't understand why George was being so obstinate about it now.
Now George shook his head and stamped his foot at his brother. "No, no, Char'ie!" he insisted. "Me George, but that Fred!" He pointed at the reflection in the mirror. "Fred!" he repeated. "How he get there?"
Suddenly, Charlie understood, and burst into laughter, only managing to stop himself when he realised that his brother was on the verge of tears. With their mother in her current mood, he did not want to be blamed for upsetting George, and end up on the receiving end of her wrath like poor Bill. So he stifled his laughter and knelt down beside the younger boy, putting an arm round his shoulders.
"You think that's Fred in the mirror?" he asked quietly.
George nodded, tears sparkling in his eyes. "Fred!" he repeated. "How he get in there? Get him out, Char'ie!"
"Calm down, George, calm down," Charlie said. "It's not Fred in there, it's you. It's George. Look, George, look!"
He pointed at his own reflection next to George's in the mirror. "Look, George," he said. "Look! There's Charlie there too now!"
George looked from his brother to the mirror in increasing confusion. "You in there?" he said. "But you here. You here, Char'ie!"
Charlie sighed. He had realised before now that explaining things at a two-year old level was not one of his strong points. But he had to try, before George started crying in earnest and brought their mother upstairs to see what was going on.
"Look, George," he said, waving to his own reflection in the mirror. "When I wave, Charlie in the mirror waves too. It's a reflection."
"Fection?" George asked dubiously. "What's fection?"
"Like a copy of you in the glass," Charlie said. "Look, George, you wave at it." He waved at the mirror as he spoke and, still looking doubtful, George waved too, his expression turning to one of astonishment and then delight as the boy in the mirror waved back.
"He wave!" he cried. "He wave too, Char'ie. He wave at us!"
Charlie grinned at the look on George's face. "That's you, Georgie," he said. "He waved because you waved. It's you in there, not Fred. It's your reflection."
"Fection," George repeated slowly, a look of dawning comprehension in his eyes. "Fred have fection too, Char'ie? And Mummy? And Daddy an' Bill an' Percy an' Ronnie? All have fections?"
Charlie laughed and nodded. "Yes, George, everyone has a reflection if they look in a mirror," he said.
George frowned, obviously thinking this over. He put out a hand to his own reflection, touching the glass of the mirror. "It look like Fred," he pointed out worriedly. "Why it look like Fred, Char'ie?"
Charlie sighed. He really was no good at this. "It looks like Fred, because you look like Fred," he said as patiently as he could manage. "You're twins, identical twins. So your reflection looks like Fred."
George screwed up his face, obviously working this out. He pointed at the mirror again. "That George?" he asked, and Charlie nodded. "He look like Fred because me look like Fred?"
Charlie nodded again. "That's it Georgie," he said. "You got it!"
George smiled, and Charlie heaved a sigh of relief. Perhaps he might be able to get back to his Quidditch story now.
But George was not quite finished. "Char'ie?" he asked. "What's dentical mean?"
Charlie could hear his mother and Bill coming up the stairs, his mother still holding forth to Bill about his carelessness and irresponsibility. He thought he had done more than his share of explaining things this morning.
"Ask Mummy," he told George firmly, as he picked up his book. "She'll tell you."