"You know what, let's make you my older brother? It would make the most sense. It would give you a family and the ability to be a mentor to me. And that way we wouldn't have to create a whole family for you from whole cloth."
"Older brother? I... I guess that could work--but how much older were you thinking I'd be? Make me too much older and it'd be kinda awkward to have me living at home," said Mike sagely.
"Well, I'm sixteen, so perhaps making you my eighteen or nineteen year old older brother would make the most sense. Either a High School senior, or a College Freshman who's living at home to save money," suggested Jeff.
"High School Senior... that way I've got mostly the same schedule you do for a year or so," said Mike.
Jeff adjusted the sixteen year old body Mike was inhabiting to be eighteen, adjusted his relationship status to be Jeff's older brother, and brought down his mental development to being that of a typical eighteen year old. If Mike was going to be a High School Senior, no need to make him stand out with him acting too mature for his age. Jeff also made a few other adjustments that Mike Jr or "Junior" as their Dad preferred to call him, namely that his interests, hobbies, and scholastic achievements would come from a random mix of Jeff, Mike, and Grace (Jeff's Mom). He hit enter and then swiveled around to watch the transformation of Mike into his older brother.
Mike, who was a sixteen year old amalgamation of Jeff and Mike shifted slightly. He shot up a further four inches in height and his muscles became lean and defined as years of running cross country and track that he'd taken from Grace gave his young adult body a lean runner's build. Mike's clothes shifted to that of a faded Green Lantern screen printed symbol t-shirt, ripped jeans, all stars, and a lightweight flanel plaid shirt tied around his waist. A mixture of clothing taste he'd borrowed from Jeff and Mike that indicated he was a slightly cool geek. The next change to the room was the room acquiring a second bed across the room along with a desk with a closed laptop on it, a few wall pinup posters that Jeff assumed Mike Sr had had as a teenager. Not to mention a shelf with cross country medals and track trophies appeared as Jeff suddenly remembered that for as long as he could remember, he'd always shared a room with his brother Mikey. Mikey in fact was what Jeff always called his brother--even as Mikey had outgrown the use of the nickname as he'd gotten older. Mikey still let Jeff call him by the nickname as it had shifted from something to be embarrassed about to a sign of affection between the two brothers--Mikey likewise responded with his own pedantic childish nickname for Jeff: Jeffy.
"Whoa... I feel different from that transformation... so much more than I was before--if that makes sense, Jeffy," said Mikey with a certain smirk stretching across his face.