Petunia Dursley really had no idea what to do with this new baby. She had never intended to have more than one child—her having a sister had ruined her own life after all. She wanted Dudley to grow up privileged and happy, to never know pain or fear or disappointment as she had. She would protect him from the world and everything in if the need arose.
This new baby though, she had no fierce love for him. The scar worried her but did not pain her as it would have if it had been on her own son's forehead. She had to keep him though, had to 'protect' him, as the bearded man in robes had made clear.
He looked like his parents, which was even worse. He had that ugly sooty hair that her brother-in-law had, and eyes that were too-green. At least he was quiet though. He had not cried or uttered a noise upon being brought into the house. Perhaps he would at least be manageable in his raising.
The babe's name was Harry Potter, he had cheated death as his parents did not, and he was to live here. Petunia carried him upstairs and contemplated what to do. Dudley had just moved out of a crib and into a toddler bed, so they could use the old furniture they had not yet disposed of. She still had some of his baby clothes too, and other things, like diapers and formula, could be bought.
Her husband sat on their bed taking his shoes off and didn't look up when she came in the room.
"Who was that at the door at this hour? It seems awfully late for visitors." She looked down at the little wrapped bundle that was quietly sleeping.
"My sister and her husband are dead," and saying the words out loud made it real, final, and although she had thought her sister annoying, she had still been her blood. Her ears rang lightly as her husband's head snapped up to stare at her.
"Harry survived," and she moved her arms a little to indicate the baby them, "and we're to raise him." She set her chin in that way that her husband knew that this was not to be argued about. Yes, neither of them wanted another child; yes, this was an unforeseen expense; yes they had no idea what to do with a wizard child. But this would happen.
Vernon dragged the crib down and set it in the smaller spare room. He would move the other furniture out in the morning, but for tonight the crib would stand at the foot of the bed.
Petunia laid him in it, untucking his wrapping to be used as a blanket. Yes it was summer, but they had been having a cold spell lately. She looked around the room, wondering if she should sleep in here lest he cry and wake little Dudley, or if she should go back to her own bed.
The baby only slept for the next half hour, and she deemed it safe to tiptoe back down the hall to her own room. Dudley hadn't woken either, and Vernon was asleep as she changed into a nightdress and slipped into bed beside him.
How to explain this to the neighbors, and to Dudley? She couldn't tell them the real story, but an altered version would do. People died everyday doing ordinary things like...driving cars! The story would become that his parents had died in a car crash and he had survived, being in the back seat. Of course his aunt would take him in.
She refused to be his mother though. The same altered story would be told to him the minute he said the word "Mama" or "Papa". They would live with this, make it alright, and still be happy somehow.
The baby must have been nursed recently, because they were able to get to the store and get diapers and formula before he got too needy. Petunia fed her son downstairs and then left him in his playpen with toys while she fed Harry. She was determined to wipe away any magic he possessed, and then maybe the boys could be friends. If not though, she would keep them as separate as possible, even if they did live in the same house.
The children would grow up, she knew, and have questions. She would provide answers, possibly not correct ones, but answers none the less. She would make her family perfectly normal and acceptable, even with this new addition.