"First," Ty said, "we need to change you a bit. Before that, though, I wish that everyone excet myself will now ignore any and all wishes that I make, unless I want them to acknowledge them. Even then, nobody wll freak out. Tnis starts with these wishes, with Sam knowing that I can wish for things, but not thinking that it is bad in any way."
That done, Ty turned his attention to his young companion.
"Would you like to grow up some, Sam?" Ty asked.
"Sure!" she squealed excitedly.
"Alright then. I wish that Sam will age to 15 human years with her breasts stopping growth at C cups. I also wish that I will age to 16 human years, but leaving my genitals(including breasts) unchanged."
Instantly, Ty shot up roughly two inches, while not much else changed. It was a different story with Sam though. Shooting upwards, Sam quickly became curvy in all the right places, hair starting to grow in her armpits and crotch, before it was shaven clean. Her hips widened and her butt puxhed out into two perfect handfuls as her hair rapidly grew til, it nearly touched her new bum. Finally, her chest puffed up and out, forming perfect C cup breasts.
Finished growing, Sam fondled her new assests, bouncing her breasts, and gasping as she rammed her fingers into her suddenly mature pussy, new sensations flooding her.