"Hey Jeff, What're you making for dinner... Jeff?" The bedroom door had swung open, banging against the dresser as their younger brother, Max burst into the room, hungry as usual. Ash quickly bent to pull his jeans back up, fumbling to adjust his new equipment and not get anything caught in the zipper. "Who... what're you doing in my brother's bedroom?!" Max had stopped in the doorway at the sight of the large man standing by the closet. "Where's Jeff?!"
Ash held out a hand "Max! Wait, I'm uh, we... we can explain!"
Drawn by the commotion, Jess appeared in the hallway behind their seven year old brother. "You're gonna love it, Max!" The boy spun, taking in the unfamiliar girl who looked to be about his age.
"Who... who are you guys? Where are my brother and sister?"
"We're right here, buddy." Jess said, reaching for his hand to draw him into the bedroom. "It's me, Jeff." At Max's look of disbelief, she tried to think of the best way for them to prove themselves. "Listen, I got this crazy cool computer program, and Ashley and I were trying it out. That's Ash - she's our 24 year-old big brother now!" Max was wide-eyed, but he wasn't bolting; Jess made a mental note to make sure their parents reinforced some 'stranger-danger' training at a later date, but for now, this was good. "Okay, how can we prove it to you?"
"He's got a birthmark on the back of his left thigh, and yesterday he snuck a turtle we found in the woods into his bedroom and has been feeding it lettuce." Ash had crossed his arms and remained by the closet, still feeling like he took up way more space than normal.
Max instantly scowled "Hey! You said you wouldn't tell anyone about Reptar! Wait... so it's really you guys? Ashley?!" He looked with wonder at the muscular man his 10 year old sister had become. "And you're really Jeff?" he asked, turning towards the young girl wearing some vaguely familiar clothes.
"Yes!" Jess laughed. "I held you as a tiny baby when I was nine, which is actually one year older than I am right now." she continued to giggle, loving the way joy just seemed to bubble up from within in her new form. Becoming a kid again had been a great idea!
"So, how did you guys... what's this program?"
Jess darted over to the computer, pulling out the chair and beckoning Max to take a seat. "You've GOTTA try it, bro! You can change anything! Make yourself older, younger, bigger, smaller, obviously you can swap genders, and there's even sections for animal, plant and inanimate options! You could turn yourself into a turtle and go hang out with your secret pet for the weekend!"
"Jess figured with Mom and Dad gone for the weekend, we could really experiment with the program, try things out and just change back before they get home Sunday night." Ash intoned, his deep voice still a shock to his siblings. "So what'll it be, Max? What do you want to change?"