holding the wand you pondered how the thing even worked. You thought "make her boobs bigger..." then flung the wand at Sis and a bit of a light ball shot out of the wand and hit Sis. Her body glowed a bit and said something on the phone along the lines of "i'll call you back" as she started noticing a tingling sensation on her breasts. Her already big breasts were slowly growing turning already into E-cups from D-cups. As they were growing larger her tank top was stretching and her nipples were starting to show. You noticed that her boobs weren't stopping from growing and thought "So I've probably got to say stop or put a limit..." her boobs were at G-cups and had burst through the tank top. he thought "Stop growing her boobs." then flung the wand and a second light ball hit Sis stopping her growth. Trying out the growth some more you thought "grow her butt and gut" and Sis started panicking some more as she got a lot more junk in the trunk and her belly starting to make her look pregnant.
Thinking about what he wanted to now he decided too...