The morning after the Dursley family received Charlie's letter, Charlotte woke thinking the whole thing had been a strange dream. After all, a wizard school? What a very odd concept, and whoever heard of such a thing? However, she couldn't put her normally level-headed husband's behavior out of her head. It hadn't just been his uncharacteristic hesitation and silence, or the slight tremors she’d seen running through his hands as he read the letter—it had also been the pasty, greenish tint to his skin as he'd trudged up the stairs.
It had also been that he hadn't come to bed until nearly four in the morning.
This last bit was, in particular, why Charlotte was so surprised to find Dudley already awake and downstairs by the time she got up. Dudley always slept in on Saturdays, never mind going to bed at such an ungodly hour. But when she walked into the kitchen to get the pancake batter started, there was Dudley, fully dressed and rummaging loudly through the junk drawer.
"Good morning, Dudley darling," Charlotte said, trying to mask her uncertainty with cheerfulness. Dudley grunted in response. His wife hesitated, but she hadn't been married to Dudley Dursley for fourteen years just to let him ignore her when strange things were afoot. She marched right up to her husband and exclaimed, "Dudley, for heaven's sake, what is going on? We get some funny trick letter and suddenly you're—"
"Where’s my cousin's last letter?" Dudley interrupted her. Charlotte couldn't have been silenced any faster if Dudley had put his hand over her mouth. Her jaw snapped shut and her eyes bulged in surprise as he, not receiving a response, turned back to the drawer. He sifted through papers, rubber bands, a broken noisemaker of Charlie's, paper clips, refrigerator magnets, and a few old Christmas cards, looking for one very specific letter.
Dudley had sat by Charlie's bedside until after three in the morning, talking with his son about the letter. Charlie had been, in turns, confused, angry, incredulous, and finally, excited. After leaving his son, Dudley had tossed back another strong drink, tried and failed to get a few hours of sleep, and finally admitted to himself that if Charlie wanted to go to that school, there was nothing for it. So now, despite the fact that Harry Potter hadn't been mentioned in his house for nine years, he was searching high and low for the last message his cousin had sent him.
Charlotte watched Dudley tear through the junk drawer with increasing frustration, until it gradually dawned on her that she wasn't going to get answers to any of her questions until her husband was through with whatever he was trying to accomplish. In hopes of ending his preoccupation, she went to the study and, thanks to her uncommonly efficient organizational skills, returned only a few moments later with the letter in question.
Dudley took the letter from his wife with a brief nod of gratitude, and sat down at the table with it. Looking over the birth announcement for Lily Luna Potter, suppressing a shudder as the picture on it blinked, he found what he was looking for: his cousin’s address.
Grabbing a pad of paper in a decidedly disgruntled fashion, Dudley penned as much of a note as he could stand:
This is your fault, you know.
Don’t suppose you've got a ruddy owl I can borrow before July 31st?
Hoping Potter would be confused by his brevity so he could, at least, get some amusement out of this bloody situation, Dudley trudged off to find an envelope and post the letter.