I will happily accept any theories you may have regarding the events of my story. Reader input has always been my favorite part of this site and it hasn't failed me yet.
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After a couple of weeks, during which Ash insisted that everyone in town refer to his daughter as "Miss Ketchum", since neither of them know her first name, Ash finally received a notification in the mail from the Pokemon League. His application had been accepted and renovations on the Gym were going to be underway shortly to reach League standards while complying with Ash's request for it's set up. Ash was so excited at the news that he decided to bust out his new grill, which was a moving in gift from one of the towns residents, who Ash only recently realized was the same one he made a scene with during his very first visit to Neon Town. Of course, thinking about that got him thinking about Jigglypuff, which he was certain was still following him.
Ash placed the grill on the table and his daughter stared at it in awe. An indoor grill was definitely a rare sight for a Pokemon trainer, but it certainly didn't warrant that kind of reaction, but Ash let it slide since it was probably her first time seeing one since losing her memories. Ash pulled out a container of meat. This meat in particular was shipped all the way from Sinnoh, making it difficult to come by in Kanto, so Ash saved it for special occasions. Just as he placed the first piece on the grill, causing a satisfying sizzle to fill the room, the door buzzer went off. Pikachu, knowing full well that Ash, unlike Brock or Cilan, needed to focus 100% on cooking for his food to be edible, went over to perch Ash had set up for him by the intercom. He pushed the "Talk" button.
"Pika?" Pikachu quizzically spoke.
"Hi Pikachu," Ash went rigid at the sound of his mothers voice, "I'm here with Professor Oak, can you let us in?"
Ash had completely forgotten that League protocol dictated that the region's leading professor would be informed of new Gym Leaders before the New Leader themselves, and Professor Oak would have been sure to tell Ash's mom immediately. Now Ash had no time to prepare for them, not to mention he hadn't even called his mom this whole time to tell her she was a grandmother. Ash did the only thing he could do, keep his focus on cooking and hope that they would be understanding of his lack of communication the past couple weeks. It took few moments between Pikachu unlocking the main door and Ash's visitors stepping into the apartment. As soon as the door opened, his daughter was on her feet.
"Hello," she greeted her grandmother and the professor, "It's a pleasure to meet you both. I'm sorry I can't introduce myself, but I can't remember my own name."
The elders were taken aback by the sight of the girl and looked at Ash for an answer.
"Surprise," Ash said with feigned excitement, "turns out I'm a dad."
Professor Oaks surprise was the first to fade. He greeted the girl and walked over to the table to speak to Ash as Delia started gushing over her adorable granddaughter. Professor Oak placed his satchel on the table.
"Congratulations Ash," Professor Oak opened his satchel, "It's not everyday I get to see one of the trainers I sent off become a Gym Leader."
"Thanks professor," Ash commented moving the freshly cooked meat to a plate.
"Yes, well, if you're going to run a fire type Gym, I think these will be important." Professor Oak pulled seven Pokeballs out of the satchel, which immediately burst open.
Ash face curled into a huge smile at the sight of his fire type Pokemon. Charizard, Quilava, Torkoal, Infernape, Pignite, Talonflame and Torracat were all ecstatic to see their trainer, so much so that Torkoal started crying and filled the room with smoke. Ash opened a window to clear the smoke and everyone sat down to eat. While Ash and Professor Oak talked about what the Gym was going to be like, Vulpix approached Charizard. Both Pokemon identified each other as their respective trainer's first fire type and, without a single sound or move, sparked a relationship akin to that of their trainers.
"By the way," Professor Oak turned to Ash's daughter, "Have you caught any Pokemon since you've been here?"
"No," She shook her head, "Vulpix is my only one, I think. I might have more with mom, but I don't know."
"Speaking of her mother," Delia looked at Ash, "Do you have any idea who she could be."
"My only clue is that she isn't from Kanto or Johto," Ash explained, "beyond that, nothing."
"Right," Professor Oak nodded, "Well, changing the subject. There are two challengers I want you to be wary of when you open the Gym Ash."
"Who?"
"The current Kanto champion, Red, who also happens to be your doppelganger, and his daughter, Scarlet, who intends to collect her Gym Badges from the extra Gyms, rather than the main eight."
"Why would Red challenge a Gym if he's already the champion?" Ash asked.
"To test their mettle. That said, I would like to see your Gym when it's ready."
"Sure, the renovations should be done this time next week."
"Then I'll see you then."
...
The day before his Gym's grand opening, Ash took his daughter for a walk through the forest outside of town.
"Seeing as we don't know whether you're here on a journey or not, I think you should catch another fire type so you can help me out in the Gym."
"You really want my help?" she asked.
"Of course." Ash smiled, "Now, Ponyta are more common in the plains, but Officer Jenny said she caught her Growlithe in this area. I think you should try to catch one too."
"You think I can do it?"
"I believe in you, and so does Vulpix." Vulpix rubbed up against her leg to prove his point, "Trust your Pokemon, they won't let you down."
"Okay dad," Hearing his words of confidence filled her with some of her own, "Let's go Vulpix!"
Ash watched his daughter and her partner run off the path and into the brush. He was confident that she would catch not only Growlithe, but another friend too.
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If you have any thoughts on what Ash's daughter's team should be, or who her mother is, feel free to share your thoughts.