Disclaimer: I don't own Harry Potter or any of the characters or places associated with the story. They are the property of JK Rowling, etc. This a nonprofit, fan based work.
At first glance the pair making their way through King Cross station appeared perfectly normal, thank you very much. The last people you would expect to be involved in anything strange or mysterious as they seemed the no-nonsense, sensible type. One was a rather large, muscular man sporting a blond walrus mustache just showing the first signs of graying. The other was a boy, young, maybe only eleven or so, but tall for his age and solidly built. He possessed enough of the man's features, blond mop of hair, watery blue eyes, for it to presumed the pair were father and son. Yes, at first glance, they seemed normal enough. However, upon closer examination, a few oddities could be detected, the most prominent of which was a large caged shaped object perched atop the boy's trunk. Though the contents of the cage had been covered with a cloth, every once in a while, they let out a doleful noise, sounding very much like a hoot.
The father paused for a moment in front of the barrier between platforms nine and ten and slid the letter out from his pocket. He scanned it two or three times before turning to his son and nodding. The boy nodded back, his face unusually serious for someone his age. He began to run, pushing the trolley in front of him, heading straight towards the barrier. He winced, expecting at any moment to feel the front of the trolley hit concrete, but instead, opened his eyes to find himself on the other side. His father reappeared behind him a moment later.
"Fantastic," the boy breathed, looking up at the large scarlet engine before him. The steam from it shrouded nearly all of the platform, but every once in a while a man or woman, or entire family would emerge from it in various stages of bustle. The two of them moved closer the side of the engine.
"Well, Mark, I'll see at the Holidays," Dudley Dursley said, trying not reveal his apprehension.
"Dad," Mark said. "Everything will be fine."
"Course' it will," Dudley replied, ruffling his son's hair. "You're your father's son, aren't you?"
Mark beamed, "You bet!"
"Well then, let me help you get settled, and then I'll see you off." Dudley lifted his son's trunk off the trolley, leaving Mark to grab the owl. He approached the train, heaving the trunk up onto the steps.
"Want help with that?" a jovial voice asked from behind.
"Sure," Dudley grunted, turning to face a man with a rather overabundance of red hair and freckles. Together they hoisted the trunk up into the train. "Thanks," Dudley said, nodding politely. The red-haired man returned the nod and made his way back through the crowd, taking the arm of a woman with mousy brown hair as he went. Dudley then turned to Mark, embracing his son for a brief (and if he were to be honest, awkward) moment.
"Have a good year son."
"Kay' Dad," Mark replied, smiling.
Dudley stood for an uncomfortable moment alone on the platform, looking around himself. As he did so, he spotted, a few cars down, a rather familiar shock of black hair. The shock of black hair turned, and the two cousins faced each other. The other waved, and Dudley waved back.
Then, he saw Mark, waving enthusiastically from a train window.
"Don't forget to write!" he called. "I didn't buy you that ruddy owl for nothing!"
Mark laughed, "I won't!"Then the train pulled away, carrying with it, the first magical child ever to have been descended from Vernon Dursley.
A story based off of an interview in which JK Rowling stated that she thought about having a little bit in the epilogue that had Dudley Dursley with a magical child on platform 9 3/4. This is my take on that unwritten anecdote.
For anyone wondering by the way Mark's full name is Markus Even Dursley, which is where the title came from. And the name itself is based off the name of one of the kids that Dudley beat up when he was younger; Mark Evans.
